FOUS30 KWBC 311600
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1200 PM EDT Thu Oct 31 2024

Day 1
Valid 16Z Thu Oct 31 2024 - 12Z Fri Nov 01 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST...

16Z Excessive Rainfall Discussion Update...
Only changes was a slight westward expansion of the Marginal risk
area near the Gulf of Mexico in far southeast Texas in response to
radar trends late this morning. There has been an area of enhanced
moisture flux convergence from far eastern Texas into northwestern
Louisiana during the morning which has led to some locally=20
enhanced rainfall rates with MRMS showing 3-hour totals at or above
2 inches in eastern Texas...with 3+ inches depicted in Fort Bend
and Brazoria counties. Showers and thunderstorms were already
anticipated in the Lower Mississippi Valley as mid- and upper-level
height falls and an associated surface cold front moves across the
area...with the potential for localized heavier rainfall rates
already anticipated from slow moving super cells...so the expansion
of the Marginal Risk area does not represent a significant shift in
forecast reasoning but merely accounting for short term conditions.

Bann

0830Z Excessive Rainfall Discussion...

As an upper-level trough advances through the Upper Midwest an
attendant cold front will makes its way from the Southern Plains
into the Lower and Middle Mississippi Valley. The front will slow
and/or stall most significantly into the Lower MS Valley, where
instability is expected to be maximized (while the flow and
associated forcing weakens farther north). Convection is expected
to be ongoing along and ahead of the cold front through morning,
but should increase in coverage and intensity during the afternoon
hours (while locally slowing the most from the Mid-South into
portions of the Deep South and Central Gulf Coast.With PWs nearing
2" (well above the 90th percentile, per SPC sounding climatology)
with storm motions locally as slow as 5-10 kts, the 00z HREF 40-km
neighborhood probabilities for 3"/3-hr reach as high as 20-40%.
While localized totals of only 1-2" are generally expected, the
HREF PMM QPF indicates the potential for isolated 3-4" totals (in
as little as 2-3 hours, nearing associated FFG thresholds).

Churchill/Campbell


Day 2
Valid 12Z Fri Nov 01 2024 - 12Z Sat Nov 02 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS AND ADJACENT SOUTHERN ROCKIES...

Another shortwave trough will move inland across the West on Friday
as ridging stays in place over much of the Southeastern US. Warm
Gulf moisture will be advecting northward into the southern High
Plains ahead of the trough. Meanwhile, the strongest instability
(1000+ J/kg of SB CAPE) will likely be in place over West Texas
and eastern New Mexico. Areal coverage of thunderstorms is forecast
to increase during the overnight hours (after 00z) into portions
of southeastern NM and the TX Panhandle, propagating eastward into
portions of western OK Oklahoma and far southern Kansas. Maintained
the Marginal Risk from prior cycles, given PWs increasing to 1.0"+
(above the 90th percentile, per SPC sounding climatology). While
most CAMs still do not reach out to the timeframe of interest, the
ones that do (the FV3 and CMCreg) suggest the potential for
localized 3"+ totals, as well as support from the downscaled ECMWF.
Decided to maintain the Marginal for this cycle, given considerable
uncertainty and dry antecedent soil conditions.

Churchill/Campbell


Day 3
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS...

A much more potent longwave trough is progged to dig into the
Southwest US on Day 2, as leading shortwave impulses are expected
to result in much more organized convection over much of the
Southern Plains. Continued southerly low-level flow ahead of the
impulses should result in PWs pushing 2" (near record levels, per
SPC sounding climatology) with ample forcing (left exit region of
100+ kt subtropical jet streak) for organizing convection. The WPC
QPF calls for areal average totals of 2-3", which is still well
below the 90th percentile of the PQPF (~4-5"). Given strong
ensemble support, the inherited Slight Risk was expanded a bit
(with the expectation of verification on the higher-end of the
Slight Risk probability spectrum from Northwest TX/Big Country into south-central OK). Given very dry antecedent conditions, a Slight
Risk was deemed sufficient (but will need to be reevaluated for
upgrade potential with future updates).

Churchill


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!498KYsnzp1R1HOg4pM5wd0Izh5EEqCKuJ1tleuhHzAib= coHm93f5eHyaJAEGD4YPlwkBeB2WbJcSIviKokxu78zP7dI$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!498KYsnzp1R1HOg4pM5wd0Izh5EEqCKuJ1tleuhHzAib= coHm93f5eHyaJAEGD4YPlwkBeB2WbJcSIviKokxuDEKGQP4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!498KYsnzp1R1HOg4pM5wd0Izh5EEqCKuJ1tleuhHzAib= coHm93f5eHyaJAEGD4YPlwkBeB2WbJcSIviKokxuav2emzQ$=20

=3D =3D =3D
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FOUS30 KWBC 312020
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
420 PM EDT Thu Oct 31 2024

Day 1
Valid 16Z Thu Oct 31 2024 - 12Z Fri Nov 01 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE LOWER MISSISSIPPI VALLEY AND CENTRAL GULF COAST...

16Z Excessive Rainfall Discussion Update...
Only changes was a slight westward expansion of the Marginal risk
area near the Gulf of Mexico in far southeast Texas in response to
radar trends late this morning. There has been an area of enhanced
moisture flux convergence from far eastern Texas into northwestern
Louisiana during the morning which has led to some locally
enhanced rainfall rates with MRMS showing 3-hour totals at or above
2 inches in eastern Texas...with 3+ inches depicted in Fort Bend
and Brazoria counties. Showers and thunderstorms were already
anticipated in the Lower Mississippi Valley as mid- and upper-level
height falls and an associated surface cold front moves across the
area...with the potential for localized heavier rainfall rates
already anticipated from slow moving super cells...so the expansion
of the Marginal Risk area does not represent a significant shift in
forecast reasoning but merely accounting for short term conditions.

Bann

0830Z Excessive Rainfall Discussion...

As an upper-level trough advances through the Upper Midwest an
attendant cold front will makes its way from the Southern Plains
into the Lower and Middle Mississippi Valley. The front will slow
and/or stall most significantly into the Lower MS Valley, where
instability is expected to be maximized (while the flow and
associated forcing weakens farther north). Convection is expected
to be ongoing along and ahead of the cold front through morning,
but should increase in coverage and intensity during the afternoon
hours (while locally slowing the most from the Mid-South into
portions of the Deep South and Central Gulf Coast.With PWs nearing
2" (well above the 90th percentile, per SPC sounding climatology)
with storm motions locally as slow as 5-10 kts, the 00z HREF 40-km
neighborhood probabilities for 3"/3-hr reach as high as 20-40%.
While localized totals of only 1-2" are generally expected, the
HREF PMM QPF indicates the potential for isolated 3-4" totals (in
as little as 2-3 hours, nearing associated FFG thresholds).

Churchill/Campbell


Day 2
Valid 12Z Fri Nov 01 2024 - 12Z Sat Nov 02 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS AND ADJACENT SOUTHERN ROCKIES...

2030Z Update...
Introduced a targeted Slight Risk area in southeast New Mexico
where an uptick in model QPF and model-derived ingredients overlap
with an area that was soaked less than 2 weeks ago and remains
hydrologically sensitive...with the expectation that the risk is
best late in the period and continuing into the Day 3 period. The
maximum Areal average rainfall amount looks to be around an
inch...which normally wouldn't warrant a Slight (especially with
the given the high flash flood guidance being so high). But with
the trends of increasing precipitable water, thetae and model QPF=20
over over and near the site of the flash flood...felt a Slight was=20 appropriate here while a Marginal remained more appropriate=20
elsewhere from the plains of southeast New Mexico to western=20
Oklahoma.

Bann

0830Z Excessive Rainfall Discussion...

Another shortwave trough will move inland across the West on Friday
as ridging stays in place over much of the Southeastern US. Warm
Gulf moisture will be advecting northward into the southern High
Plains ahead of the trough. Meanwhile, the strongest instability
(1000+ J/kg of SB CAPE) will likely be in place over West Texas
and eastern New Mexico. Areal coverage of thunderstorms is forecast
to increase during the overnight hours (after 00z) into portions
of southeastern NM and the TX Panhandle, propagating eastward into
portions of western OK Oklahoma and far southern Kansas. Maintained
the Marginal Risk from prior cycles, given PWs increasing to 1.0"+
(above the 90th percentile, per SPC sounding climatology). While
most CAMs still do not reach out to the timeframe of interest, the
ones that do (the FV3 and CMCreg) suggest the potential for
localized 3"+ totals, as well as support from the downscaled ECMWF.
Decided to maintain the Marginal for this cycle, given considerable
uncertainty and dry antecedent soil conditions.

Churchill/Campbell


Day 3
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS...

2030Z Update...
Few changes were needed given fairly decent run to run agreement
with the scenario of a much more potent longwave trough digging
into the Southwest US that results in more organized convection
capable of producing heavy rainfall. Opted to not to jump all the
way to the full extent suggested by the ML ERO guidance...but felt
an expanded areal coverage was warranted based on the placement
suggested by spaghetti plots of QPF from the ensembles as well as
the global models combined with the idea that the rainfall on Day 3
will function to prime the soils for more runoff/flooding potential
on Day 4 and beyond. Will continue to watch how much overlap there
is and upgrade if necessary. Until then...thinking is that the risk
from Saturday into early Sunday is a high-end Slight Risk from
parts of Oklahoma into far north Texas.

Bann


0830Z Excessive Rainfall Discussion...

A much more potent longwave trough is progged to dig into the
Southwest US on Day 2, as leading shortwave impulses are expected
to result in much more organized convection over much of the
Southern Plains. Continued southerly low-level flow ahead of the
impulses should result in PWs pushing 2" (near record levels, per
SPC sounding climatology) with ample forcing (left exit region of
100+ kt subtropical jet streak) for organizing convection. The WPC
QPF calls for areal average totals of 2-3", which is still well
below the 90th percentile of the PQPF (~4-5"). Given strong
ensemble support, the inherited Slight Risk was expanded a bit
(with the expectation of verification on the higher-end of the
Slight Risk probability spectrum from Northwest TX/Big Country into south-central OK). Given very dry antecedent conditions, a Slight
Risk was deemed sufficient (but will need to be reevaluated for
upgrade potential with future updates).

Churchill


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9tc5csKwVqasJcVi2mOW2ZLzgu62FCEPDpEOkA90rPPK= eZBYI7RDqJvHfg7vecSU3wSKf17JFGEbjfbf2BJNAgwevZE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9tc5csKwVqasJcVi2mOW2ZLzgu62FCEPDpEOkA90rPPK= eZBYI7RDqJvHfg7vecSU3wSKf17JFGEbjfbf2BJN4yCbD3M$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9tc5csKwVqasJcVi2mOW2ZLzgu62FCEPDpEOkA90rPPK= eZBYI7RDqJvHfg7vecSU3wSKf17JFGEbjfbf2BJN1HlI_hA$=20

=3D =3D =3D
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FOUS30 KWBC 010038
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
838 PM EDT Thu Oct 31 2024

Day 1
Valid 01Z Fri Nov 01 2024 - 12Z Fri Nov 01 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
LOUISIANA AND MISSISSIPPI...

A Marginal risk remains from portions of central LA into southern
and central MS. Localized cell mergers and training may result in a
few instances of flash flooding over portions of these areas.

PWs around 2" and MLCAPE of 1000 j/kg are supportive of efficient
rainfall with a few instances if 2-3" per hour rainfall expected
where cells briefly train. Some cell merging and training is
expected over portions of southwest to south central MS through=20
the evening hours where a slowing line of convection is=20
intersecting cells moving northward within an axis of southerly=20
flow. Guidance indicates that the axis of enhanced convergence that
is driving this threat should weaken within a few hours, with=20
convective intensity also decreasing. However the MCV that is=20
evident over central LA may help sustain this convergence a bit=20
longer than the HRRR indicates...and do think isolated 2-4" amounts
within a couple hours are possible.

Instability is a tad higher over LA, and convergence near the
remnant MCV may linger longer here. While differing in location
from run to run, recent HRRR runs indicate the potential for a few
slow moving convective cells/clusters over central LA tonight. In
the HRRR these cells are anchoring near the instability
gradient/boundary and are able to persist long enough to produce
localized amounts in excess of 6". Confidence in only average at=20
best, but the HRRR scenario is plausible given the setup and=20
ingredients in place. The main question will be whether the MCV=20
stays pronounced enough to support continued low level moisture=20 transport/convergence into the instability gradient.

Dry antecedent conditions have resulted in high FFG values over=20
the region. Thus flash flood issues should generally stay very=20
localized in nature and focused within any more sensitive urban=20
areas where excess runoff from these heavy rates is more likely.=20
However if the HRRR scenario of 6"+ amounts over portions of LA=20
pans out overnight, then a more robust flash flood threat could=20
evolve, so will need to monitor trends through the overnight hours.

Chenard


Day 2
Valid 12Z Fri Nov 01 2024 - 12Z Sat Nov 02 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS AND ADJACENT SOUTHERN ROCKIES...

2030Z Update...
Introduced a targeted Slight Risk area in southeast New Mexico
where an uptick in model QPF and model-derived ingredients overlap
with an area that was soaked less than 2 weeks ago and remains
hydrologically sensitive...with the expectation that the risk is
best late in the period and continuing into the Day 3 period. The
maximum Areal average rainfall amount looks to be around an
inch...which normally wouldn't warrant a Slight (especially with
the given the high flash flood guidance being so high). But with
the trends of increasing precipitable water, thetae and model QPF
over over and near the site of the flash flood...felt a Slight was
appropriate here while a Marginal remained more appropriate
elsewhere from the plains of southeast New Mexico to western
Oklahoma.

Bann

0830Z Excessive Rainfall Discussion...

Another shortwave trough will move inland across the West on Friday
as ridging stays in place over much of the Southeastern US. Warm
Gulf moisture will be advecting northward into the southern High
Plains ahead of the trough. Meanwhile, the strongest instability
(1000+ J/kg of SB CAPE) will likely be in place over West Texas
and eastern New Mexico. Areal coverage of thunderstorms is forecast
to increase during the overnight hours (after 00z) into portions
of southeastern NM and the TX Panhandle, propagating eastward into
portions of western OK Oklahoma and far southern Kansas. Maintained
the Marginal Risk from prior cycles, given PWs increasing to 1.0"+
(above the 90th percentile, per SPC sounding climatology). While
most CAMs still do not reach out to the timeframe of interest, the
ones that do (the FV3 and CMCreg) suggest the potential for
localized 3"+ totals, as well as support from the downscaled ECMWF.
Decided to maintain the Marginal for this cycle, given considerable
uncertainty and dry antecedent soil conditions.

Churchill/Campbell


Day 3
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS...

2030Z Update...
Few changes were needed given fairly decent run to run agreement
with the scenario of a much more potent longwave trough digging
into the Southwest US that results in more organized convection
capable of producing heavy rainfall. Opted to not to jump all the
way to the full extent suggested by the ML ERO guidance...but felt
an expanded areal coverage was warranted based on the placement
suggested by spaghetti plots of QPF from the ensembles as well as
the global models combined with the idea that the rainfall on Day 3
will function to prime the soils for more runoff/flooding potential
on Day 4 and beyond. Will continue to watch how much overlap there
is and upgrade if necessary. Until then...thinking is that the risk
from Saturday into early Sunday is a high-end Slight Risk from
parts of Oklahoma into far north Texas.

Bann


0830Z Excessive Rainfall Discussion...

A much more potent longwave trough is progged to dig into the
Southwest US on Day 2, as leading shortwave impulses are expected
to result in much more organized convection over much of the
Southern Plains. Continued southerly low-level flow ahead of the
impulses should result in PWs pushing 2" (near record levels, per
SPC sounding climatology) with ample forcing (left exit region of
100+ kt subtropical jet streak) for organizing convection. The WPC
QPF calls for areal average totals of 2-3", which is still well
below the 90th percentile of the PQPF (~4-5"). Given strong
ensemble support, the inherited Slight Risk was expanded a bit
(with the expectation of verification on the higher-end of the
Slight Risk probability spectrum from Northwest TX/Big Country into south-central OK). Given very dry antecedent conditions, a Slight
Risk was deemed sufficient (but will need to be reevaluated for
upgrade potential with future updates).

Churchill


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5_UoLTmQYR0fuAD228hQet4eWbUzO9WiC5fyKCKwxcHw= fxofNhFm06fWd8KK9UIOapAq20XbRJXjHNI_w7wmcIEChU0$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5_UoLTmQYR0fuAD228hQet4eWbUzO9WiC5fyKCKwxcHw= fxofNhFm06fWd8KK9UIOapAq20XbRJXjHNI_w7wm6vDvbpI$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5_UoLTmQYR0fuAD228hQet4eWbUzO9WiC5fyKCKwxcHw= fxofNhFm06fWd8KK9UIOapAq20XbRJXjHNI_w7wmFbu04ek$=20

=3D =3D =3D
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FOUS30 KWBC 010810
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
410 AM EDT Fri Nov 1 2024

Day 1
Valid 12Z Fri Nov 01 2024 - 12Z Sat Nov 02 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR A SMALL PORTION
OF SOUTHEASTERN NEW MEXICO...

...New Mexico and the TX/OK Panhandles...

A digging trough over the intermountain west will begin to tap into
building Gulf moisture across eastern New Mexico and the Texas and
Oklahoma Panhandles. With interactions with upper level energy,
CAMs guidance is highlighting the Slight risk area from the
Sacramento Mountains to the Texas state line for the heaviest
rains. The whole area has been very dry in recent weeks (as has
most of the country), so that should greatly mitigate the flash
flooding threat. Further, the guidance isn't in perfect agreement
on where the heaviest rains will occur...though the Slight risk
highlights where most of the guidance is. Thus...the threat is most
certainly still on the lower end of the Slight risk scale.

The storms that form over New Mexico will train northeastward
across the Panhandles. Where repetitive training can occur,
isolated flash flooding is possible, but the storms will be
stronger further south and west.

...Louisiana/Mississippi...

A convergence zone is likely to set up across the Mississippi Delta
Friday night. Slow moving convection is expected, though that
convection would likely need to move over an urban or flood
sensitive area to cause localized flash flooding. With HREF
probabilities for 3 inches of rain Friday night over 50%, a
Marginal Risk area was added with this update.

Wegman

Day 2
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

Additional Gulf moisture will track north on a LLJ across Texas and
into the Slight Risk area on Saturday. PWATs may exceed 1.75
inches. The trough over the intermountain west will slow to a
crawl, while much faster moving shortwaves round the base of the
trough and move north up the Plains. Multiple rounds of storms are
expected from north Texas to the Kansas City metro. The heaviest
rains are likely across central Oklahoma, where a higher-end Slight
is in place.=20

As on Day 1, extremely dry antecedent conditions are in place over
much of the Slight Risk area, with soil moisture levels from Nasa
Sport at under 10%. While clay soils may start out hydrophobic, for
the most part, the empty creeks and streams should work to prevent
much flash flooding. Given the available moisture for the storms to
work with, training is likely, which should raise the flash
flooding potential to widely scattered. The Slight Risk area was=20
expanded a bit towards the northeast and now approaches the Kansas=20
City metro. Meanwhile a portion of north Texas was removed based on
the latest guidance. Nonetheless a slower forward progression of=20
the entire pattern should concentrate the worst impacts from any=20
flash flooding in a smaller corridor highlighted by the Slight=20
Risk. No major changes were made to the inherited risk areas. The=20
greatest uncertainty is how well the dry soils will absorb the
sudden abundance of moisture as the drought conditions in place now
across the southern Plains will help in many cases to mitigate any
potential flooding impacts.

Wegman

Day 3
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN OKLAHOMA AND THE OZARKS...

The inherited Moderate Risk area was shifted to the southeast a few
rows of counties in Oklahoma with this update. This is in response
to the latest guidance suggesting the heaviest rainfall will
fall more across eastern Oklahoma through the Ozarks of western
Missouri. A big factor as to the flooding potential will be
rainfall from the Day 2/Saturday period, which alone is expected to
result in a widespread 3-5 inches of rain across the Moderate Risk
area. When added to the 2-4 inches of rain expected Sunday for many
of the same areas, even the antecedent drought conditions in place
now should not be able to handle two consecutive days of heavy
rain. The primary point of uncertainty is how much overlap there
will be between the two days. The slow moving nature of the entire
system should mean much of the Moderate Risk area will be in the
overlap. Urban and flood sensitive areas are likely to have the
greatest risk of impacts from training storms, with the strongest
storms and heaviest rains expected Sunday night. The storms will
continue north and east across northern Missouri and into Iowa and
Illinois, where the Slight Risk was extended based partially on
prior days' rainfall. Regardless, outside of the Moderate Risk
area, antecedent dry conditions will have a bigger mitigating
impact on the flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!54mpqT3n57o0nOYn5Oa0v6NeexwhDKGcs-BP52INK_g4= cwIShh9y9kHEesIq-q_au8ooRHXiP0z2JZVKpr7MauwQpu0$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!54mpqT3n57o0nOYn5Oa0v6NeexwhDKGcs-BP52INK_g4= cwIShh9y9kHEesIq-q_au8ooRHXiP0z2JZVKpr7M1KWR96o$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!54mpqT3n57o0nOYn5Oa0v6NeexwhDKGcs-BP52INK_g4= cwIShh9y9kHEesIq-q_au8ooRHXiP0z2JZVKpr7MMzbwIts$=20

=3D =3D =3D
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FOUS30 KWBC 011555
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1155 AM EDT Fri Nov 1 2024

Day 1
Valid 16Z Fri Nov 01 2024 - 12Z Sat Nov 02 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR A SMALL PORTION
OF SOUTHEASTERN NEW MEXICO...

16Z Excessive Rainfall Outlook Discussion...
No changes needed to either the Slight/Marginal risk areas
southeast New Mexico and adjacent portions of the Texas/Oklahoma
panhandles or with the Marginal risk area along the immediate Gulf
coast. With trough amplification over the western United States now underway...flow across the Gulf coast region should begin to
back...allowing for moisture to return northward/westward leading
to expanding coverage over the southern High Plains late tonight.
Dry antecedent conditions should mitigate the risk of excessive
rainfall in most areas...with the biggest exception being in
southeast New Mexico which remains hydrologically sensitive
following significant flash flooding less than 2 week ago. So made
no changes to the Slight Risk area that was already in place...and
only minor nudges to the perimeter of the Marginal risk area.
Farther east...the HREF continues to suggest additional convection
is possible later today that will have the potential for isolated
rainfall rates of 1 inch per hour...and even a low probability of 2
inch per hour rates immediately west of Lake Pontchartrain late=20
this afternoon/early evening. So no significant change made with=20
that Marginal risk area.

Bann

...New Mexico and the TX/OK Panhandles...

A digging trough over the intermountain west will begin to tap into
building Gulf moisture across eastern New Mexico and the Texas and
Oklahoma Panhandles. With interactions with upper level energy,
CAMs guidance is highlighting the Slight risk area from the
Sacramento Mountains to the Texas state line for the heaviest
rains. The whole area has been very dry in recent weeks (as has
most of the country), so that should greatly mitigate the flash
flooding threat. Further, the guidance isn't in perfect agreement
on where the heaviest rains will occur...though the Slight risk
highlights where most of the guidance is. Thus...the threat is most
certainly still on the lower end of the Slight risk scale.

The storms that form over New Mexico will train northeastward
across the Panhandles. Where repetitive training can occur,
isolated flash flooding is possible, but the storms will be
stronger further south and west.

...Louisiana/Mississippi...

A convergence zone is likely to set up across the Mississippi Delta
Friday night. Slow moving convection is expected, though that
convection would likely need to move over an urban or flood
sensitive area to cause localized flash flooding. With HREF
probabilities for 3 inches of rain Friday night over 50%, a
Marginal Risk area was added with this update.

Wegman

Day 2
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

Additional Gulf moisture will track north on a LLJ across Texas and
into the Slight Risk area on Saturday. PWATs may exceed 1.75
inches. The trough over the intermountain west will slow to a
crawl, while much faster moving shortwaves round the base of the
trough and move north up the Plains. Multiple rounds of storms are
expected from north Texas to the Kansas City metro. The heaviest
rains are likely across central Oklahoma, where a higher-end Slight
is in place.

As on Day 1, extremely dry antecedent conditions are in place over
much of the Slight Risk area, with soil moisture levels from Nasa
Sport at under 10%. While clay soils may start out hydrophobic, for
the most part, the empty creeks and streams should work to prevent
much flash flooding. Given the available moisture for the storms to
work with, training is likely, which should raise the flash
flooding potential to widely scattered. The Slight Risk area was
expanded a bit towards the northeast and now approaches the Kansas
City metro. Meanwhile a portion of north Texas was removed based on
the latest guidance. Nonetheless a slower forward progression of
the entire pattern should concentrate the worst impacts from any
flash flooding in a smaller corridor highlighted by the Slight
Risk. No major changes were made to the inherited risk areas. The
greatest uncertainty is how well the dry soils will absorb the
sudden abundance of moisture as the drought conditions in place now
across the southern Plains will help in many cases to mitigate any
potential flooding impacts.

Wegman

Day 3
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN OKLAHOMA AND THE OZARKS...

The inherited Moderate Risk area was shifted to the southeast a few
rows of counties in Oklahoma with this update. This is in response
to the latest guidance suggesting the heaviest rainfall will
fall more across eastern Oklahoma through the Ozarks of western
Missouri. A big factor as to the flooding potential will be
rainfall from the Day 2/Saturday period, which alone is expected to
result in a widespread 3-5 inches of rain across the Moderate Risk
area. When added to the 2-4 inches of rain expected Sunday for many
of the same areas, even the antecedent drought conditions in place
now should not be able to handle two consecutive days of heavy
rain. The primary point of uncertainty is how much overlap there
will be between the two days. The slow moving nature of the entire
system should mean much of the Moderate Risk area will be in the
overlap. Urban and flood sensitive areas are likely to have the
greatest risk of impacts from training storms, with the strongest
storms and heaviest rains expected Sunday night. The storms will
continue north and east across northern Missouri and into Iowa and
Illinois, where the Slight Risk was extended based partially on
prior days' rainfall. Regardless, outside of the Moderate Risk
area, antecedent dry conditions will have a bigger mitigating
impact on the flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5woD2AVX70sKGA1_6RABw_cX87AgpUt5W1jreO_OW9gT= CzSHlWNncZNkIzaXWPlTqHWFUDF_ZFpER3EVePYNdCyDIf4$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5woD2AVX70sKGA1_6RABw_cX87AgpUt5W1jreO_OW9gT= CzSHlWNncZNkIzaXWPlTqHWFUDF_ZFpER3EVePYN1TPyB_4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5woD2AVX70sKGA1_6RABw_cX87AgpUt5W1jreO_OW9gT= CzSHlWNncZNkIzaXWPlTqHWFUDF_ZFpER3EVePYNgpdyw88$=20

=3D =3D =3D
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FOUS30 KWBC 012029
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
429 PM EDT Fri Nov 1 2024

Day 1
Valid 16Z Fri Nov 01 2024 - 12Z Sat Nov 02 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR A SMALL PORTION
OF SOUTHEASTERN NEW MEXICO...

16Z Excessive Rainfall Outlook Discussion...
No changes needed to either the Slight/Marginal risk areas
southeast New Mexico and adjacent portions of the Texas/Oklahoma
panhandles or with the Marginal risk area along the immediate Gulf
coast. With trough amplification over the western United States now underway...flow across the Gulf coast region should begin to
back...allowing for moisture to return northward/westward leading
to expanding coverage over the southern High Plains late tonight.
Dry antecedent conditions should mitigate the risk of excessive
rainfall in most areas...with the biggest exception being in
southeast New Mexico which remains hydrologically sensitive
following significant flash flooding less than 2 week ago. So made
no changes to the Slight Risk area that was already in place...and
only minor nudges to the perimeter of the Marginal risk area.
Farther east...the HREF continues to suggest additional convection
is possible later today that will have the potential for isolated
rainfall rates of 1 inch per hour...and even a low probability of 2
inch per hour rates immediately west of Lake Pontchartrain late
this afternoon/early evening. So no significant change made with
that Marginal risk area.

Bann

Previous Discussion...
...New Mexico and the TX/OK Panhandles...

A digging trough over the intermountain west will begin to tap into
building Gulf moisture across eastern New Mexico and the Texas and
Oklahoma Panhandles. With interactions with upper level energy,
CAMs guidance is highlighting the Slight risk area from the
Sacramento Mountains to the Texas state line for the heaviest
rains. The whole area has been very dry in recent weeks (as has
most of the country), so that should greatly mitigate the flash
flooding threat. Further, the guidance isn't in perfect agreement
on where the heaviest rains will occur...though the Slight risk
highlights where most of the guidance is. Thus...the threat is most
certainly still on the lower end of the Slight risk scale.

The storms that form over New Mexico will train northeastward
across the Panhandles. Where repetitive training can occur,
isolated flash flooding is possible, but the storms will be
stronger further south and west.

...Louisiana/Mississippi...

A convergence zone is likely to set up across the Mississippi Delta
Friday night. Slow moving convection is expected, though that
convection would likely need to move over an urban or flood
sensitive area to cause localized flash flooding. With HREF
probabilities for 3 inches of rain Friday night over 50%, a
Marginal Risk area was added with this update.

Wegman

Day 2
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

2030Z Excessive Rainfall Discussion Update...
There was a subtle westward/southward shift in the axis of heaviest
rainfall shown in the 12Z numerical suite of guidance. The axis of
the high-end Slight risk area was elongated in a similar fashion
with a more subtle shift in the axis, The expectation about the
very dry antecedent conditions helping to mitigate the overall
excessive rainfall impacts still hold.

Bann


Previous Discussion...

Additional Gulf moisture will track north on a LLJ across Texas and
into the Slight Risk area on Saturday. PWATs may exceed 1.75
inches. The trough over the intermountain west will slow to a
crawl, while much faster moving shortwaves round the base of the
trough and move north up the Plains. Multiple rounds of storms are
expected from north Texas to the Kansas City metro. The heaviest
rains are likely across central Oklahoma, where a higher-end Slight
is in place.

As on Day 1, extremely dry antecedent conditions are in place over
much of the Slight Risk area, with soil moisture levels from Nasa
Sport at under 10%. While clay soils may start out hydrophobic, for
the most part, the empty creeks and streams should work to prevent
much flash flooding. Given the available moisture for the storms to
work with, training is likely, which should raise the flash
flooding potential to widely scattered. The Slight Risk area was
expanded a bit towards the northeast and now approaches the Kansas
City metro. Meanwhile a portion of north Texas was removed based on
the latest guidance. Nonetheless a slower forward progression of
the entire pattern should concentrate the worst impacts from any
flash flooding in a smaller corridor highlighted by the Slight
Risk. No major changes were made to the inherited risk areas. The
greatest uncertainty is how well the dry soils will absorb the
sudden abundance of moisture as the drought conditions in place now
across the southern Plains will help in many cases to mitigate any
potential flooding impacts.

Wegman

Day 3
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN OKLAHOMA AND THE OZARKS...

2030Z Excessive Rainfall Discussion Update...
The 12Z suite of guidance offered good support for the placement of
the Moderate Risk area. Uncertainty remains as to exactly how well
the dry soils will absorb the rainfall and exactly how much of an
overlap there will be with the rainfall on Saturday. The model run
to run consistency to maintain the Moderate risk outlook area.

Bann

Previous Discussion...

The inherited Moderate Risk area was shifted to the southeast a few
rows of counties in Oklahoma with this update. This is in response
to the latest guidance suggesting the heaviest rainfall will
fall more across eastern Oklahoma through the Ozarks of western
Missouri. A big factor as to the flooding potential will be
rainfall from the Day 2/Saturday period, which alone is expected to
result in a widespread 3-5 inches of rain across the Moderate Risk
area. When added to the 2-4 inches of rain expected Sunday for many
of the same areas, even the antecedent drought conditions in place
now should not be able to handle two consecutive days of heavy
rain. The primary point of uncertainty is how much overlap there
will be between the two days. The slow moving nature of the entire
system should mean much of the Moderate Risk area will be in the
overlap. Urban and flood sensitive areas are likely to have the
greatest risk of impacts from training storms, with the strongest
storms and heaviest rains expected Sunday night. The storms will
continue north and east across northern Missouri and into Iowa and
Illinois, where the Slight Risk was extended based partially on
prior days' rainfall. Regardless, outside of the Moderate Risk
area, antecedent dry conditions will have a bigger mitigating
impact on the flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_MPg9EKJXjwcygoaNgTM_PuVOLSmZSnXOkUGdeb912xZ= jBv3dv1A3m1o83i7WI_4vsUMtiCMFMDkvXspi7sSoR90Y7A$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_MPg9EKJXjwcygoaNgTM_PuVOLSmZSnXOkUGdeb912xZ= jBv3dv1A3m1o83i7WI_4vsUMtiCMFMDkvXspi7sShZ56E-M$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_MPg9EKJXjwcygoaNgTM_PuVOLSmZSnXOkUGdeb912xZ= jBv3dv1A3m1o83i7WI_4vsUMtiCMFMDkvXspi7sSr8SMtk8$=20

=3D =3D =3D
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FOUS30 KWBC 020041
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
841 PM EDT Fri Nov 1 2024

Day 1
Valid 01Z Sat Nov 02 2024 - 12Z Sat Nov 02 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF=20
SOUTHEASTERN NEW MEXICO INTO FAR WEST TEXAS...

Training convection this evening has resulted in isolated flash
flooding across portions of central LA. HRRR guidance indicates=20
the convergence axis driving this activity should weaken over the=20
next couple hours, with convective intensity and training=20
potential expected to diminish as well. Cloud tops are beginning to
show some signs of warming, so maybe this weakening trend is=20
beginning. Nonetheless, a localized flash flood risk is possible=20
for the next several hours.

Otherwise attention turns to portions of southeast NM for the
overnight hours into Saturday morning. An increasing and robust
southeasterly low level jet is rapidly returning moisture into the
region, and convergence on the nose of this moisture transport=20
axis should help initiate convection within the next several=20
hours. Larger scale forcing in the form an an approaching longwave
trough and upper jet streak to the north should increase=20
overnight, which should help convection grow upscale in nature=20
after 06z. Some southwest to northeast training appears likely, and
as is seemingly often the case over this region, would not be=20
surprised if convective coverage ends up a bit larger than depicted
by the HRRR. Overall expect 1-3" of rainfall through 12z Saturday,
but a narrow swath of 3-6" seems possible along the convergence=20
axis where training is maximized.=20

Recent HRRR runs have trended a bit north with the maximum=20
QPF swath in recent runs, and so have also expanded the Slight risk
in this direction as well. Will not cut back on the southern=20
extent of the Slight risk as some model guidance still favors this
corridor. Overall the updated Slight risk encompasses the model=20
spread and the bit broader nature accounts for the potential of a=20
more organized convective area as the night progresses.

Chenard


Day 2
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

2030Z Excessive Rainfall Discussion Update...
There was a subtle westward/southward shift in the axis of heaviest
rainfall shown in the 12Z numerical suite of guidance. The axis of
the high-end Slight risk area was elongated in a similar fashion
with a more subtle shift in the axis, The expectation about the
very dry antecedent conditions helping to mitigate the overall
excessive rainfall impacts still hold.

Bann


Previous Discussion...

Additional Gulf moisture will track north on a LLJ across Texas and
into the Slight Risk area on Saturday. PWATs may exceed 1.75
inches. The trough over the intermountain west will slow to a
crawl, while much faster moving shortwaves round the base of the
trough and move north up the Plains. Multiple rounds of storms are
expected from north Texas to the Kansas City metro. The heaviest
rains are likely across central Oklahoma, where a higher-end Slight
is in place.

As on Day 1, extremely dry antecedent conditions are in place over
much of the Slight Risk area, with soil moisture levels from Nasa
Sport at under 10%. While clay soils may start out hydrophobic, for
the most part, the empty creeks and streams should work to prevent
much flash flooding. Given the available moisture for the storms to
work with, training is likely, which should raise the flash
flooding potential to widely scattered. The Slight Risk area was
expanded a bit towards the northeast and now approaches the Kansas
City metro. Meanwhile a portion of north Texas was removed based on
the latest guidance. Nonetheless a slower forward progression of
the entire pattern should concentrate the worst impacts from any
flash flooding in a smaller corridor highlighted by the Slight
Risk. No major changes were made to the inherited risk areas. The
greatest uncertainty is how well the dry soils will absorb the
sudden abundance of moisture as the drought conditions in place now
across the southern Plains will help in many cases to mitigate any
potential flooding impacts.

Wegman

Day 3
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN OKLAHOMA AND THE OZARKS...

2030Z Excessive Rainfall Discussion Update...
The 12Z suite of guidance offered good support for the placement of
the Moderate Risk area. Uncertainty remains as to exactly how well
the dry soils will absorb the rainfall and exactly how much of an
overlap there will be with the rainfall on Saturday. The model run
to run consistency to maintain the Moderate risk outlook area.

Bann

Previous Discussion...

The inherited Moderate Risk area was shifted to the southeast a few
rows of counties in Oklahoma with this update. This is in response
to the latest guidance suggesting the heaviest rainfall will
fall more across eastern Oklahoma through the Ozarks of western
Missouri. A big factor as to the flooding potential will be
rainfall from the Day 2/Saturday period, which alone is expected to
result in a widespread 3-5 inches of rain across the Moderate Risk
area. When added to the 2-4 inches of rain expected Sunday for many
of the same areas, even the antecedent drought conditions in place
now should not be able to handle two consecutive days of heavy
rain. The primary point of uncertainty is how much overlap there
will be between the two days. The slow moving nature of the entire
system should mean much of the Moderate Risk area will be in the
overlap. Urban and flood sensitive areas are likely to have the
greatest risk of impacts from training storms, with the strongest
storms and heaviest rains expected Sunday night. The storms will
continue north and east across northern Missouri and into Iowa and
Illinois, where the Slight Risk was extended based partially on
prior days' rainfall. Regardless, outside of the Moderate Risk
area, antecedent dry conditions will have a bigger mitigating
impact on the flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5kmUC1SiAotJQqvC9m6TUNm7Jf4ADeIfkR2nhhQM7Ju2= l4G2TBzZuHq_bBaqLU-8qxmrkUzUcjfhtOsvvgzzFUbXPMc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5kmUC1SiAotJQqvC9m6TUNm7Jf4ADeIfkR2nhhQM7Ju2= l4G2TBzZuHq_bBaqLU-8qxmrkUzUcjfhtOsvvgzziP_rrww$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5kmUC1SiAotJQqvC9m6TUNm7Jf4ADeIfkR2nhhQM7Ju2= l4G2TBzZuHq_bBaqLU-8qxmrkUzUcjfhtOsvvgzz8U9ole4$=20

=3D =3D =3D
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FOUS30 KWBC 020814
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
414 AM EDT Sat Nov 2 2024

Day 1
Valid 12Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF=20
THE SOUTHERN PLAINS...

A deep but slow-moving longwave trough will move across the Desert
Southwest through tonight. Multiple shortwaves of upper level=20
energy will move through the jet stream rounding the base of the=20
trough. As those shortwaves eject over the high Plains of Texas and
Oklahoma, they will meet up with increasing Gulf moisture tracking
northward across Texas. At the surface, the trough-ridge interface
will feature a slow-moving cold front which will also add to the
forcing in the area. PWATs will increase above 1.75 inches across
much of the Slight Risk area.

The combination of the increasing moisture and ample low and upper
level forcing will be multiple rounds of training thunderstorms
initiating over northwest Texas and the Panhandle, then quickly
organize into segments which will slowly track east as embedded
heavier cells track northeastward and roughly parallel to the
lines. This will support training convection which in addition to 2
inch per hour rates, could mean any particular location in the=20
Slight Risk area could see multiple rounds of heavy rainfall.

In contrast to the heavy rains, mitigating the flood risk has been
multiple weeks of very little rain across the middle of the
country. The dry streams and creekbeds will easily be able to
handle most of the rain that falls, but should training of multiple
storms occur, especially over any urban areas such as Oklahoma
City, then flash flooding impacts could quickly arise. Since the
storms will be slow moving, this will support widely scattered
flooding impacts, especially from Wichita Falls, TX through
Oklahoma City.=20

Wegman

Day 2
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FROM CENTRAL AND
NORTHEASTERN OKLAHOMA AND ALONG THE KANSAS/MISSOURI BORDER...

Storms from the overnight period Saturday night will diminish with
daytime heating and the typical daytime weakening of the LLJ.
However, throughout the day the atmosphere will recharge such that
by Sunday night the passage of another shortwave will result in a
refiring of the storms across central and eastern Oklahoma, which
will grow and train upscale into far eastern Kansas, Missouri, and
eventually Iowa and far western Illinois. The Moderate Risk was
largely unchanged, with a small northward expansion. This is
primarily the portion of the region which is expected to get some
rain tonight, which will prime the soils for the heavier rains for
most of eastern Oklahoma and points north and east by Sunday night.
This expected overlap of rainfall is what will push the flash
flooding impact and coverage potential into the Moderate Risk
category, albeit the lower end of the category. Obviously this will
largely depend on how much rain is seen in the Moderate Risk area
Saturday night before the start of the period.

Once again the LLJ off the Gulf will supply a stream of ample
moisture to the slow-moving storms, so the flooding impact
potential, especially in areas where Sunday is the first
significant rains seen in the area in weeks, will be dependent on
the upper level energy tracking along the surface front keeping
storms moving over the same areas. The ERO risk areas were
conservative on the north and east sides and more liberal on the
south and west sides due to expected prior rainfall (or lack
thereof) on Saturday. The lack of prior rainfall has gotten river
levels to very low conditions, making plenty of room for the water
from heavy rain. This will greatly diminish the flooding threat
broadly. Had there been recent rains in this area, then a more
expansive Moderate Risk may have been needed. From Day 2 onward the
flooding potential across the middle of the country will be highly
dependent on how well previous days rains were able to result in
flooding, as amounts in the highest rainfall risk areas will be
largely the same day to day, so overlap with previous' days will be
critical. Of course, urban and low-lying/flood prone areas will be
at greater risk of flash flooding through Sunday night.

Wegman

Day 3
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH THE CHICAGOLAND AREA...

The slow moving cold front that will have brought rains to areas
west of the Mississippi this weekend will move a little faster to
the east Monday and Monday night. Additional lines of storms are
expected again on Monday, but mostly for areas not expected to get
too much rain this weekend. Thus, the Slight Risk remains good as
the flooding from heavy rain is offset by the dry soil conditions.
By this point we should have a good idea as to how much flooding
will be seen as both Saturday and Sunday's forecast rains will be
on repeat over the Slight Risk area again on Monday. No significant
changes were made or needed from the inherited Day 4 forecast.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8NeRbExZA1MgVkKj78BhUMvehFS_rxn5EHxFnOcplCUp= KVhM6znXXgp7V4u-cdieRJipl3Nn6anrM4GQRiMiJB7FKlY$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8NeRbExZA1MgVkKj78BhUMvehFS_rxn5EHxFnOcplCUp= KVhM6znXXgp7V4u-cdieRJipl3Nn6anrM4GQRiMiKgziAwk$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8NeRbExZA1MgVkKj78BhUMvehFS_rxn5EHxFnOcplCUp= KVhM6znXXgp7V4u-cdieRJipl3Nn6anrM4GQRiMiNEId9tg$=20

=3D =3D =3D
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FOUS30 KWBC 021600
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1200 PM EDT Sat Nov 2 2024

Day 1
Valid 16Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS...

...16z update...

The previous discussion captures the excessive rainfall threat
well. Minor adjustments were made to the day 1 ERO as a result. The
slight risk area was expanded on the southwestern and northern
peripheries to account for increased QPF signals in the 06/12z CAMs.

Kebede


...Previous Discussion...

A deep but slow-moving longwave trough will move across the Desert
Southwest through tonight. Multiple shortwaves of upper level
energy will move through the jet stream rounding the base of the
trough. As those shortwaves eject over the high Plains of Texas and
Oklahoma, they will meet up with increasing Gulf moisture tracking
northward across Texas. At the surface, the trough-ridge interface
will feature a slow-moving cold front which will also add to the
forcing in the area. PWATs will increase above 1.75 inches across
much of the Slight Risk area.

The combination of the increasing moisture and ample low and upper
level forcing will be multiple rounds of training thunderstorms
initiating over northwest Texas and the Panhandle, then quickly
organize into segments which will slowly track east as embedded
heavier cells track northeastward and roughly parallel to the
lines. This will support training convection which in addition to 2
inch per hour rates, could mean any particular location in the
Slight Risk area could see multiple rounds of heavy rainfall.

In contrast to the heavy rains, mitigating the flood risk has been
multiple weeks of very little rain across the middle of the
country. The dry streams and creekbeds will easily be able to
handle most of the rain that falls, but should training of multiple
storms occur, especially over any urban areas such as Oklahoma
City, then flash flooding impacts could quickly arise. Since the
storms will be slow moving, this will support widely scattered
flooding impacts, especially from Wichita Falls, TX through
Oklahoma City.

Wegman

Day 2
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FROM CENTRAL AND
NORTHEASTERN OKLAHOMA AND ALONG THE KANSAS/MISSOURI BORDER...

Storms from the overnight period Saturday night will diminish with
daytime heating and the typical daytime weakening of the LLJ.
However, throughout the day the atmosphere will recharge such that
by Sunday night the passage of another shortwave will result in a
refiring of the storms across central and eastern Oklahoma, which
will grow and train upscale into far eastern Kansas, Missouri, and
eventually Iowa and far western Illinois. The Moderate Risk was
largely unchanged, with a small northward expansion. This is
primarily the portion of the region which is expected to get some
rain tonight, which will prime the soils for the heavier rains for
most of eastern Oklahoma and points north and east by Sunday night.
This expected overlap of rainfall is what will push the flash
flooding impact and coverage potential into the Moderate Risk
category, albeit the lower end of the category. Obviously this will
largely depend on how much rain is seen in the Moderate Risk area
Saturday night before the start of the period.

Once again the LLJ off the Gulf will supply a stream of ample
moisture to the slow-moving storms, so the flooding impact
potential, especially in areas where Sunday is the first
significant rains seen in the area in weeks, will be dependent on
the upper level energy tracking along the surface front keeping
storms moving over the same areas. The ERO risk areas were
conservative on the north and east sides and more liberal on the
south and west sides due to expected prior rainfall (or lack
thereof) on Saturday. The lack of prior rainfall has gotten river
levels to very low conditions, making plenty of room for the water
from heavy rain. This will greatly diminish the flooding threat
broadly. Had there been recent rains in this area, then a more
expansive Moderate Risk may have been needed. From Day 2 onward the
flooding potential across the middle of the country will be highly
dependent on how well previous days rains were able to result in
flooding, as amounts in the highest rainfall risk areas will be
largely the same day to day, so overlap with previous' days will be
critical. Of course, urban and low-lying/flood prone areas will be
at greater risk of flash flooding through Sunday night.

Wegman

Day 3
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH THE CHICAGOLAND AREA...

The slow moving cold front that will have brought rains to areas
west of the Mississippi this weekend will move a little faster to
the east Monday and Monday night. Additional lines of storms are
expected again on Monday, but mostly for areas not expected to get
too much rain this weekend. Thus, the Slight Risk remains good as
the flooding from heavy rain is offset by the dry soil conditions.
By this point we should have a good idea as to how much flooding
will be seen as both Saturday and Sunday's forecast rains will be
on repeat over the Slight Risk area again on Monday. No significant
changes were made or needed from the inherited Day 4 forecast.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!83fy-bWWv1Kur9TAq75h5oq_13iEmtcAf2bCQrWKZeDF= KSUwPyP_KVYsSb7xGhT-TvNf52AGohKM3Iyqw_tt7jKHjB4$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!83fy-bWWv1Kur9TAq75h5oq_13iEmtcAf2bCQrWKZeDF= KSUwPyP_KVYsSb7xGhT-TvNf52AGohKM3Iyqw_ttTQSwsp0$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!83fy-bWWv1Kur9TAq75h5oq_13iEmtcAf2bCQrWKZeDF= KSUwPyP_KVYsSb7xGhT-TvNf52AGohKM3Iyqw_ttFylgohw$=20

=3D =3D =3D
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FOUS30 KWBC 022022
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
422 PM EDT Sat Nov 2 2024

Day 1
Valid 16Z Sat Nov 02 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS...

...16z update...

The previous discussion captures the excessive rainfall threat
well. Minor adjustments were made to the day 1 ERO as a result. The
slight risk area was expanded on the southwestern and northern
peripheries to account for increased QPF signals in the 06/12z CAMs.

Kebede


...Previous Discussion...

A deep but slow-moving longwave trough will move across the Desert
Southwest through tonight. Multiple shortwaves of upper level
energy will move through the jet stream rounding the base of the
trough. As those shortwaves eject over the high Plains of Texas and
Oklahoma, they will meet up with increasing Gulf moisture tracking
northward across Texas. At the surface, the trough-ridge interface
will feature a slow-moving cold front which will also add to the
forcing in the area. PWATs will increase above 1.75 inches across
much of the Slight Risk area.

The combination of the increasing moisture and ample low and upper
level forcing will be multiple rounds of training thunderstorms
initiating over northwest Texas and the Panhandle, then quickly
organize into segments which will slowly track east as embedded
heavier cells track northeastward and roughly parallel to the
lines. This will support training convection which in addition to 2
inch per hour rates, could mean any particular location in the
Slight Risk area could see multiple rounds of heavy rainfall.

In contrast to the heavy rains, mitigating the flood risk has been
multiple weeks of very little rain across the middle of the
country. The dry streams and creekbeds will easily be able to
handle most of the rain that falls, but should training of multiple
storms occur, especially over any urban areas such as Oklahoma
City, then flash flooding impacts could quickly arise. Since the
storms will be slow moving, this will support widely scattered
flooding impacts, especially from Wichita Falls, TX through
Oklahoma City.

Wegman

Day 2
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FROM CENTRAL AND
NORTHEASTERN OKLAHOMA AND ALONG THE KANSAS/MISSOURI BORDER...

...2030z Update...

The inherited risk areas remain mostly unchanged, save for some
minor tweaks to the northern portions of the Marginal and Slight
Risk areas. The previous discussion remains valid. 12z guidance
hasn't changed much in its presentation of the axis of QPF over the
affected regions.

Kebede

...Previous Discussion...

Storms from the overnight period Saturday night will diminish with
daytime heating and the typical daytime weakening of the LLJ.
However, throughout the day the atmosphere will recharge such that
by Sunday night the passage of another shortwave will result in a
refiring of the storms across central and eastern Oklahoma, which
will grow and train upscale into far eastern Kansas, Missouri, and
eventually Iowa and far western Illinois. The Moderate Risk was
largely unchanged, with a small northward expansion. This is
primarily the portion of the region which is expected to get some
rain tonight, which will prime the soils for the heavier rains for
most of eastern Oklahoma and points north and east by Sunday night.
This expected overlap of rainfall is what will push the flash
flooding impact and coverage potential into the Moderate Risk
category, albeit the lower end of the category. Obviously this will
largely depend on how much rain is seen in the Moderate Risk area
Saturday night before the start of the period.

Once again the LLJ off the Gulf will supply a stream of ample
moisture to the slow-moving storms, so the flooding impact
potential, especially in areas where Sunday is the first
significant rains seen in the area in weeks, will be dependent on
the upper level energy tracking along the surface front keeping
storms moving over the same areas. The ERO risk areas were
conservative on the north and east sides and more liberal on the
south and west sides due to expected prior rainfall (or lack
thereof) on Saturday. The lack of prior rainfall has gotten river
levels to very low conditions, making plenty of room for the water
from heavy rain. This will greatly diminish the flooding threat
broadly. Had there been recent rains in this area, then a more
expansive Moderate Risk may have been needed. From Day 2 onward the
flooding potential across the middle of the country will be highly
dependent on how well previous days rains were able to result in
flooding, as amounts in the highest rainfall risk areas will be
largely the same day to day, so overlap with previous' days will be
critical. Of course, urban and low-lying/flood prone areas will be
at greater risk of flash flooding through Sunday night.

Wegman

Day 3
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH THE CHICAGOLAND AREA...

...2030z Update...

The Marginal and Slight Risk areas were expanded on their northern
and southern peripheries to include parts of Michigan and more of=20
eastern Texas. PWAT anomalies in the 3-5 standard deviation range
and a substantial low level jet (50kts+) over the Upper Midwest=20
was enough to warrant an expansion of that Slight Risk into those
areas. An upgrade to a Moderate Risk area over portions of the=20
Lower Missouri Valley was considered, but ultimately not
implemented since it'll depend on how much priming occurs during
the days 1 and 2 timeframes.

Kebede

...Previous Discussion...

The slow moving cold front that will have brought rains to areas
west of the Mississippi this weekend will move a little faster to
the east Monday and Monday night. Additional lines of storms are
expected again on Monday, but mostly for areas not expected to get
too much rain this weekend. Thus, the Slight Risk remains good as
the flooding from heavy rain is offset by the dry soil conditions.
By this point we should have a good idea as to how much flooding
will be seen as both Saturday and Sunday's forecast rains will be
on repeat over the Slight Risk area again on Monday. No significant
changes were made or needed from the inherited Day 4 forecast.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8V2UW9SKMyEO4KXDg2nZQl1Uaob3OPVlJj82fsBpakvU= zmoa0lrNCAed1W81akONpe_6L3TgdybyuTAJ0ik6yBMBwGg$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8V2UW9SKMyEO4KXDg2nZQl1Uaob3OPVlJj82fsBpakvU= zmoa0lrNCAed1W81akONpe_6L3TgdybyuTAJ0ik6COwtF30$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8V2UW9SKMyEO4KXDg2nZQl1Uaob3OPVlJj82fsBpakvU= zmoa0lrNCAed1W81akONpe_6L3TgdybyuTAJ0ik6bbb5PFI$=20

=3D =3D =3D
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FOUS30 KWBC 030023
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
823 PM EDT Sat Nov 2 2024

Day 1
Valid 01Z Sun Nov 03 2024 - 12Z Sun Nov 03 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHERN PLAINS...


A deep, slow-moving longwave trough will move across the Desert=20
Southwest through tonight. Multiple shortwaves of upper level=20
energy will move through the jet stream rounding the base of the=20
trough. As those shortwaves eject over the High Plains of Texas=20
and Oklahoma, they will meet up with increasing Gulf moisture=20
tracking northward across Texas. At the surface, the trough-ridge=20
interface will feature a slow-moving cold front which will also add
to the forcing in the area. PWATs increase above 1.75 inches=20
across much of the Slight Risk area.

The combination of the increasing moisture and ample low and upper
level forcing will be multiple rounds of training thunderstorms
initiating over northwest Texas and the Panhandle, then quickly
organize into segments which will slowly track east as embedded
heavier cells track northeastward and roughly parallel to the
lines. This will support training convection which in addition to 2
inch per hour rates, could mean any particular location in the
Slight Risk area could see multiple rounds of heavy rainfall.

In contrast to the heavy rains, mitigating the flood risk has been
multiple weeks of very little rain across the middle of the
country. The dry streams and creekbeds will easily be able to
handle most of the rain that falls, but should training of multiple
storms occur, especially over any urban areas such as Oklahoma
City, then flash flooding impacts could quickly arise. Since the
storms will be slow moving, this will support widely scattered
flooding impacts, especially from Wichita Falls, TX through
Oklahoma City.

Changes to the previously issued outlook were to account for storm
motion and the 18z HREF hourly and 12 hourly probabilities for
heavy rainfall. This led to trimming of the northwest side of the
previously defined areas, but no change to the risk level across=20
the region as a whole.

Roth/Wegman

Day 2
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FROM CENTRAL AND
NORTHEASTERN OKLAHOMA AND ALONG THE KANSAS/MISSOURI BORDER...

...2030z Update...

The inherited risk areas remain mostly unchanged, save for some
minor tweaks to the northern portions of the Marginal and Slight
Risk areas. The previous discussion remains valid. 12z guidance
hasn't changed much in its presentation of the axis of QPF over the
affected regions.

Kebede

...Previous Discussion...

Storms from the overnight period Saturday night will diminish with
daytime heating and the typical daytime weakening of the LLJ.
However, throughout the day the atmosphere will recharge such that
by Sunday night the passage of another shortwave will result in a
refiring of the storms across central and eastern Oklahoma, which
will grow and train upscale into far eastern Kansas, Missouri, and
eventually Iowa and far western Illinois. The Moderate Risk was
largely unchanged, with a small northward expansion. This is
primarily the portion of the region which is expected to get some
rain tonight, which will prime the soils for the heavier rains for
most of eastern Oklahoma and points north and east by Sunday night.
This expected overlap of rainfall is what will push the flash
flooding impact and coverage potential into the Moderate Risk
category, albeit the lower end of the category. Obviously this will
largely depend on how much rain is seen in the Moderate Risk area
Saturday night before the start of the period.

Once again the LLJ off the Gulf will supply a stream of ample
moisture to the slow-moving storms, so the flooding impact
potential, especially in areas where Sunday is the first
significant rains seen in the area in weeks, will be dependent on
the upper level energy tracking along the surface front keeping
storms moving over the same areas. The ERO risk areas were
conservative on the north and east sides and more liberal on the
south and west sides due to expected prior rainfall (or lack
thereof) on Saturday. The lack of prior rainfall has gotten river
levels to very low conditions, making plenty of room for the water
from heavy rain. This will greatly diminish the flooding threat
broadly. Had there been recent rains in this area, then a more
expansive Moderate Risk may have been needed. From Day 2 onward the
flooding potential across the middle of the country will be highly
dependent on how well previous days rains were able to result in
flooding, as amounts in the highest rainfall risk areas will be
largely the same day to day, so overlap with previous' days will be
critical. Of course, urban and low-lying/flood prone areas will be
at greater risk of flash flooding through Sunday night.

Wegman

Day 3
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH THE CHICAGOLAND AREA...

...2030z Update...

The Marginal and Slight Risk areas were expanded on their northern
and southern peripheries to include parts of Michigan and more of
eastern Texas. PWAT anomalies in the 3-5 standard deviation range
and a substantial low level jet (50kts+) over the Upper Midwest
was enough to warrant an expansion of that Slight Risk into those
areas. An upgrade to a Moderate Risk area over portions of the
Lower Missouri Valley was considered, but ultimately not
implemented since it'll depend on how much priming occurs during
the days 1 and 2 timeframes.

Kebede

...Previous Discussion...

The slow moving cold front that will have brought rains to areas
west of the Mississippi this weekend will move a little faster to
the east Monday and Monday night. Additional lines of storms are
expected again on Monday, but mostly for areas not expected to get
too much rain this weekend. Thus, the Slight Risk remains good as
the flooding from heavy rain is offset by the dry soil conditions.
By this point we should have a good idea as to how much flooding
will be seen as both Saturday and Sunday's forecast rains will be
on repeat over the Slight Risk area again on Monday. No significant
changes were made or needed from the inherited Day 4 forecast.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!40x6J5x7F93xaDkVIDKHcqFeRxLy7VrYlqiVsJkZnkLU= mFVShQ-pJbop2yL5uS74eZY4stC5lObx0QGO2vxYPfXha7Y$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!40x6J5x7F93xaDkVIDKHcqFeRxLy7VrYlqiVsJkZnkLU= mFVShQ-pJbop2yL5uS74eZY4stC5lObx0QGO2vxYGtTQZUE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!40x6J5x7F93xaDkVIDKHcqFeRxLy7VrYlqiVsJkZnkLU= mFVShQ-pJbop2yL5uS74eZY4stC5lObx0QGO2vxY6F3LXBw$=20

=3D =3D =3D
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FOUS30 KWBC 030808
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
308 AM EST Sun Nov 3 2024

Day 1
Valid 12Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS AND THE OZARKS...

...Southern Plains and the Ozarks...

In coordination with TSA/Tulsa, OK; LZK/Little Rock, AR; and
SGF/Springfield, MO forecast offices, the inherited Moderate Risk
area was downgraded to a Slight with this update. The surrounding
Marginal was trimmed out of Wisconsin, Minnesota, and much of Iowa.=20

There was a notable south and eastward shift in the guidance as to
the axis of heaviest rainfall expected across Oklahoma and Arkansas
today into tonight. A longwave trough over the Southwest will shift
eastward today. Embedded shortwave disturbances as well as a
developing 90 kt jet streak will move over the region through
tonight. A well-established low level jet (LLJ) will continue to advect plentiful Gulf moisture northward into the area. The result will be
multiple rounds of storms with embedded training cells in OK/AR and
into MO. Much of the area has been very dry lately, though
yesterday some rain impacted the area, especially in Oklahoma and
into southern Missouri. Multiple "streaks" of much heavier rainfall
are anticipated where cells of much heavier rain train over the
same areas. This is likely to cause widely scattered to scattered
instances of flash flooding.=20

Antecedent conditions will be the primary limiting factor keeping
the flooding impacts in check. Very dry conditions prior to this
event has led to drought conditions developing with very low river
and stream levels. Thus...much of the rain expected today will be
beneficial and work to return those rivers and streams to much more
normal levels. However, given the plentiful moisture, training
storms, and some flood prone areas, the heavy rain could cause
localized flash flooding. The eastward shift in the guidance has
also introduced the Ozarks into the highest risk area. The
topography of the area will help to focus the heavy rainfall into
the valleys...which could result in rapid river, stream and creek
rises. This also locally increases the flash flooding threat as
compared to the same amount of rain falling over relatively flat
terrain.

While forecast rainfall amounts haven't changed appreciably as
compared with previous forecasts, the shift of the heaviest rain
eastward and into many areas that did not receive appreciable rain
today has reduced the likely flood impact threat as well as
coverage. When added to the dry antecedent conditions, this should
keep flooding impacts from becoming widespread enough to reach
Moderate Risk levels. Hence, while flash flooding remains likely as
amounts could locally exceed 5 inches, the impact and coverage was
determined to be in the Slight Risk category...hence the downgrade.

...Upper Midwest...

In the upper Midwest, the eastward shift in the guidance and a more
west to east movement of the expected convection should limit how
much instability and moisture reach the upper Mississippi Valley.
It's likely any remaining convection will be in a much weakened
state by the time the rain reaches this area. Since similarly dry
conditions and drought have impacted the upper Great Lakes in
recent weeks, the largely stratiform nature of the rain should mean
all of the rain will be beneficial with no flooding concerns noted.
Thus, the Marginal was trimmed towards the south.

Wegman

Day 2
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH PORTIONS OF WESTERN LOWER MICHIGAN...

Few changes were made or needed to the Slight Risk area across the
middle of the country.

A deep longwave trough will continue move eastward but begin to
weaken and lift northward back into the jet stream on Monday. As it
does so, associated jet streaks will intensify downstream of the
trough, which will support its deamplification. The LLJ that has
been supplying Gulf moisture will also elongate towards the north
reaching as far north as lower Michigan by Monday. This will cause
the resultant moisture to focus in a SSW to NNE corridor from Texas
to Michigan. Unidirectional SSW flow will support training
thunderstorms. The strongest storms are expected from Texas through
Missouri, which will have access to the greatest Gulf instability
and moisture. The storms will gradually weaken the further north
you go, but are expected to maintain their integrity into Wisconsin
and Michigan. The topography of the Ozarks will further locally
enhance rainfall totals due to some upslope support.=20

Due to overlap with the rainfall footprint Monday with that=20
expected today, there is some potential for a Moderate Risk upgrade
from western Arkansas into southern Missouri. However, this will be
highly dependent on how much rain falls in that area today/Sunday.
Total rainfall amounts will be somewhat lower on Monday as compared
to Sunday, hence the importance of rain falling over the same areas
as Sunday to enhance the flooding threat to Moderate Risk levels. Thus,
the potential for an upgrade will continue to be evaluated.

Wegman

Day 3
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

By Tuesday, a progressive cold front pushing across the Mississippi
Valley and associated upper level trough and shortwave will
separate...with the upper shortwave ejecting northeastward into the
Great Lakes, leaving the front behind. The combination of steady
forward movement of the storms through the day followed by the
rapid diminishing of any and all upper level support by Tuesday
night will rapidly diminish the flooding threat as storm coverage
and intensity also diminish. With some supply of Gulf moisture
continuing on Tuesday, the storms that form through the day will
still have enough punch to cause locally heavy rainfall. However,
the eastward progression of the front should allow this rain to
fall largely over areas that remain dry today/Sunday and Monday.
Antecedent dry conditions will preclude much of the flooding threat
by Tuesday, so only isolated flash flooding in urban and flood
prone areas is anticipated. The Marginal Risk is largely unchanged
from previous forecasts.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_-v8iTLljYp2O6xUnMo5BvoPmA3GJ_Egn4rs7HPGG0ue= C_E6rtfvyg-k827Q75xmxZ9xetgOzUPA0P8cJGxZZToUjjU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_-v8iTLljYp2O6xUnMo5BvoPmA3GJ_Egn4rs7HPGG0ue= C_E6rtfvyg-k827Q75xmxZ9xetgOzUPA0P8cJGxZanTMAd8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_-v8iTLljYp2O6xUnMo5BvoPmA3GJ_Egn4rs7HPGG0ue= C_E6rtfvyg-k827Q75xmxZ9xetgOzUPA0P8cJGxZw-14-HE$=20

=3D =3D =3D
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FOUS30 KWBC 031558
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1058 AM EST Sun Nov 3 2024

Day 1
Valid 16Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS AND THE OZARKS...

...16z Update...

Little change to the inherited Slight Risk area, owing to
observational trends and the new 12z HREF suite. The bulk of the
expected rainfall going forward looks to occur to the south and
east of areas that were hardest hit over the past 12 hours=20
(mainly central to northeast OK). Despite this, the Slight was
maintained over the wetter antecedent conditions, as elevated
convection looks to still result in scattered 2-3" totals (well
represented by the 12z HREF blended-mean, and particularly the 12z
HRRR solution). Farther south and east (into southeast OK and
northwest AR), scattered to numerous totals of 3-5" are more likely
(with isolated/localized totals of 5" possible). Drier antecedent=20
conditions across this region will likely limit instances of flash
flooding to scattered coverage, but locally significant flash=20
flooding will still be possible (considering that consecutive 3-hr
periods of 3" exceedance are progged at 20-40% after 00z, per HREF
40-km neighborhood exceedance probabilities).

Churchill


...Previous Discussion...

...Southern Plains and the Ozarks...

In coordination with TSA/Tulsa, OK; LZK/Little Rock, AR; and
SGF/Springfield, MO forecast offices, the inherited Moderate Risk
area was downgraded to a Slight with this update. The surrounding
Marginal was trimmed out of Wisconsin, Minnesota, and much of Iowa.

There was a notable south and eastward shift in the guidance as to
the axis of heaviest rainfall expected across Oklahoma and Arkansas
today into tonight. A longwave trough over the Southwest will shift
eastward today. Embedded shortwave disturbances as well as a
developing 90 kt jet streak will move over the region through
tonight. A well-established low level jet (LLJ) will continue to advect plentiful Gulf moisture northward into the area. The result will be
multiple rounds of storms with embedded training cells in OK/AR and
into MO. Much of the area has been very dry lately, though
yesterday some rain impacted the area, especially in Oklahoma and
into southern Missouri. Multiple "streaks" of much heavier rainfall
are anticipated where cells of much heavier rain train over the
same areas. This is likely to cause widely scattered to scattered
instances of flash flooding.

Antecedent conditions will be the primary limiting factor keeping
the flooding impacts in check. Very dry conditions prior to this
event has led to drought conditions developing with very low river
and stream levels. Thus...much of the rain expected today will be
beneficial and work to return those rivers and streams to much more
normal levels. However, given the plentiful moisture, training
storms, and some flood prone areas, the heavy rain could cause
localized flash flooding. The eastward shift in the guidance has
also introduced the Ozarks into the highest risk area. The
topography of the area will help to focus the heavy rainfall into
the valleys...which could result in rapid river, stream and creek
rises. This also locally increases the flash flooding threat as
compared to the same amount of rain falling over relatively flat
terrain.

While forecast rainfall amounts haven't changed appreciably as
compared with previous forecasts, the shift of the heaviest rain
eastward and into many areas that did not receive appreciable rain
today has reduced the likely flood impact threat as well as
coverage. When added to the dry antecedent conditions, this should
keep flooding impacts from becoming widespread enough to reach
Moderate Risk levels. Hence, while flash flooding remains likely as
amounts could locally exceed 5 inches, the impact and coverage was
determined to be in the Slight Risk category...hence the downgrade.

...Upper Midwest...

In the upper Midwest, the eastward shift in the guidance and a more
west to east movement of the expected convection should limit how
much instability and moisture reach the upper Mississippi Valley.
It's likely any remaining convection will be in a much weakened
state by the time the rain reaches this area. Since similarly dry
conditions and drought have impacted the upper Great Lakes in
recent weeks, the largely stratiform nature of the rain should mean
all of the rain will be beneficial with no flooding concerns noted.
Thus, the Marginal was trimmed towards the south.

Wegman

Day 2
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH PORTIONS OF WESTERN LOWER MICHIGAN...

Few changes were made or needed to the Slight Risk area across the
middle of the country.

A deep longwave trough will continue move eastward but begin to
weaken and lift northward back into the jet stream on Monday. As it
does so, associated jet streaks will intensify downstream of the
trough, which will support its deamplification. The LLJ that has
been supplying Gulf moisture will also elongate towards the north
reaching as far north as lower Michigan by Monday. This will cause
the resultant moisture to focus in a SSW to NNE corridor from Texas
to Michigan. Unidirectional SSW flow will support training
thunderstorms. The strongest storms are expected from Texas through
Missouri, which will have access to the greatest Gulf instability
and moisture. The storms will gradually weaken the further north
you go, but are expected to maintain their integrity into Wisconsin
and Michigan. The topography of the Ozarks will further locally
enhance rainfall totals due to some upslope support.

Due to overlap with the rainfall footprint Monday with that
expected today, there is some potential for a Moderate Risk upgrade
from western Arkansas into southern Missouri. However, this will be
highly dependent on how much rain falls in that area today/Sunday.
Total rainfall amounts will be somewhat lower on Monday as compared
to Sunday, hence the importance of rain falling over the same areas
as Sunday to enhance the flooding threat to Moderate Risk levels. Thus,
the potential for an upgrade will continue to be evaluated.

Wegman

Day 3
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

By Tuesday, a progressive cold front pushing across the Mississippi
Valley and associated upper level trough and shortwave will
separate...with the upper shortwave ejecting northeastward into the
Great Lakes, leaving the front behind. The combination of steady
forward movement of the storms through the day followed by the
rapid diminishing of any and all upper level support by Tuesday
night will rapidly diminish the flooding threat as storm coverage
and intensity also diminish. With some supply of Gulf moisture
continuing on Tuesday, the storms that form through the day will
still have enough punch to cause locally heavy rainfall. However,
the eastward progression of the front should allow this rain to
fall largely over areas that remain dry today/Sunday and Monday.
Antecedent dry conditions will preclude much of the flooding threat
by Tuesday, so only isolated flash flooding in urban and flood
prone areas is anticipated. The Marginal Risk is largely unchanged
from previous forecasts.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4oy93G7Li6BfSvV45-I-Ko8I5CB8QzXc1rrwDQJe9Z2R= ermzHL0LfVpB_CFBiQ9P07y8-UDTR6ky5t3QViJeqsDbIUE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4oy93G7Li6BfSvV45-I-Ko8I5CB8QzXc1rrwDQJe9Z2R= ermzHL0LfVpB_CFBiQ9P07y8-UDTR6ky5t3QViJeEnAq4u0$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4oy93G7Li6BfSvV45-I-Ko8I5CB8QzXc1rrwDQJe9Z2R= ermzHL0LfVpB_CFBiQ9P07y8-UDTR6ky5t3QViJeThwEZLg$=20

=3D =3D =3D
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FOUS30 KWBC 031958
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
258 PM EST Sun Nov 3 2024

Day 1
Valid 16Z Sun Nov 03 2024 - 12Z Mon Nov 04 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS AND THE OZARKS...

...16z Update...

Little change to the inherited Slight Risk area, owing to
observational trends and the new 12z HREF suite. The bulk of the
expected rainfall going forward looks to occur to the south and
east of areas that were hardest hit over the past 12 hours
(mainly central to northeast OK). Despite this, the Slight was
maintained over the wetter antecedent conditions, as elevated
convection looks to still result in scattered 2-3" totals (well
represented by the 12z HREF blended-mean, and particularly the 12z
HRRR solution). Farther south and east (into southeast OK and
northwest AR), scattered to numerous totals of 3-5" are more likely
(with isolated/localized totals of 5" possible). Drier antecedent
conditions across this region will likely limit instances of flash
flooding to scattered coverage, but locally significant flash
flooding will still be possible (considering that consecutive 3-hr
periods of 3" exceedance are progged at 20-40% after 00z, per HREF
40-km neighborhood exceedance probabilities).

Churchill


...Previous Discussion...

...Southern Plains and the Ozarks...

In coordination with TSA/Tulsa, OK; LZK/Little Rock, AR; and
SGF/Springfield, MO forecast offices, the inherited Moderate Risk
area was downgraded to a Slight with this update. The surrounding
Marginal was trimmed out of Wisconsin, Minnesota, and much of Iowa.

There was a notable south and eastward shift in the guidance as to
the axis of heaviest rainfall expected across Oklahoma and Arkansas
today into tonight. A longwave trough over the Southwest will shift
eastward today. Embedded shortwave disturbances as well as a
developing 90 kt jet streak will move over the region through
tonight. A well-established low level jet (LLJ) will continue to advect plentiful Gulf moisture northward into the area. The result will be
multiple rounds of storms with embedded training cells in OK/AR and
into MO. Much of the area has been very dry lately, though
yesterday some rain impacted the area, especially in Oklahoma and
into southern Missouri. Multiple "streaks" of much heavier rainfall
are anticipated where cells of much heavier rain train over the
same areas. This is likely to cause widely scattered to scattered
instances of flash flooding.

Antecedent conditions will be the primary limiting factor keeping
the flooding impacts in check. Very dry conditions prior to this
event has led to drought conditions developing with very low river
and stream levels. Thus...much of the rain expected today will be
beneficial and work to return those rivers and streams to much more
normal levels. However, given the plentiful moisture, training
storms, and some flood prone areas, the heavy rain could cause
localized flash flooding. The eastward shift in the guidance has
also introduced the Ozarks into the highest risk area. The
topography of the area will help to focus the heavy rainfall into
the valleys...which could result in rapid river, stream and creek
rises. This also locally increases the flash flooding threat as
compared to the same amount of rain falling over relatively flat
terrain.

While forecast rainfall amounts haven't changed appreciably as
compared with previous forecasts, the shift of the heaviest rain
eastward and into many areas that did not receive appreciable rain
today has reduced the likely flood impact threat as well as
coverage. When added to the dry antecedent conditions, this should
keep flooding impacts from becoming widespread enough to reach
Moderate Risk levels. Hence, while flash flooding remains likely as
amounts could locally exceed 5 inches, the impact and coverage was
determined to be in the Slight Risk category...hence the downgrade.

...Upper Midwest...

In the upper Midwest, the eastward shift in the guidance and a more
west to east movement of the expected convection should limit how
much instability and moisture reach the upper Mississippi Valley.
It's likely any remaining convection will be in a much weakened
state by the time the rain reaches this area. Since similarly dry
conditions and drought have impacted the upper Great Lakes in
recent weeks, the largely stratiform nature of the rain should mean
all of the rain will be beneficial with no flooding concerns noted.
Thus, the Marginal was trimmed towards the south.

Wegman

Day 2
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH PORTIONS OF WESTERN LOWER MICHIGAN...

20Z Update: Changes were few and far between for the D2 ERO with
the primary deviation being a slight shift eastward with the risk
areas given the latest trends within the forecast precip. A
secondary area of development over the course the evening into
tomorrow morning will generate another outflow dominant convective
pattern with a general expansion of the precip further to the north
and east leading to areas downstream in the Ozarks becoming the
benefactor of the heaviest precip. There's a strong consensus for
heavy rain totals exceeding 3" across the above area with a the 12z
HREF neighborhood probabilities exceeding 70% for the >3" threshold
extending from Southeast OK up through Northwest and North-Central
AR into Southeastern MO. EAS probabilities follow suit with an axis
of 50+% of >2" probs located over the same area with a 20-30% for

3" encompassing a good portion of the Ozarks. The antecedent

conditions leading in are relatively dry in the grand scheme with
the NASA SPoRT indicators leveling off the soil moisture
percentiles below 40% for much of the area anticipating heavy rain.
The more complex terrain does offer a slightly better risk than
typical compared to areas in the plains, so the prospects are
within the higher end of the SLGT risk margin, but just outside the
MDT risk upgrade for the time being. Pending the evolution of the
activity tonight, an upgrade may be necessary, targeting locations
likely centered over Northwest AR into Southern MO. Will continue
to monitor the situation closely as it evolves.=20

..Previous Forecast..

Few changes were made or needed to the Slight Risk area across the
middle of the country.

A deep longwave trough will continue move eastward but begin to
weaken and lift northward back into the jet stream on Monday. As it
does so, associated jet streaks will intensify downstream of the
trough, which will support its deamplification. The LLJ that has
been supplying Gulf moisture will also elongate towards the north
reaching as far north as lower Michigan by Monday. This will cause
the resultant moisture to focus in a SSW to NNE corridor from Texas
to Michigan. Unidirectional SSW flow will support training
thunderstorms. The strongest storms are expected from Texas through
Missouri, which will have access to the greatest Gulf instability
and moisture. The storms will gradually weaken the further north
you go, but are expected to maintain their integrity into Wisconsin
and Michigan. The topography of the Ozarks will further locally
enhance rainfall totals due to some upslope support.

Due to overlap with the rainfall footprint Monday with that
expected today, there is some potential for a Moderate Risk upgrade
from western Arkansas into southern Missouri. However, this will be
highly dependent on how much rain falls in that area today/Sunday.
Total rainfall amounts will be somewhat lower on Monday as compared
to Sunday, hence the importance of rain falling over the same areas
as Sunday to enhance the flooding threat to Moderate Risk levels. Thus,
the potential for an upgrade will continue to be evaluated.

Wegman

Day 3
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

20Z Update: Very minor adjustments were made to the MRGL risk
located across the Mississippi and Ohio Valleys as the overall
pattern and subsequent rainfall forecast maintained continuity from
run-to-run. Areal average QPF runs between 1-2" for the period with
the heaviest rainfall likely relegated over the Mid Mississippi
Valley Tuesday morning and afternoon before petering out as the
disturbance shifts eastward. Main threats will be relegated to
mainly urban and small stream flooding with more isolated flash
flood concerns in terms of an areal extent.

..Previous Forecast..

By Tuesday, a progressive cold front pushing across the Mississippi
Valley and associated upper level trough and shortwave will
separate...with the upper shortwave ejecting northeastward into the
Great Lakes, leaving the front behind. The combination of steady
forward movement of the storms through the day followed by the
rapid diminishing of any and all upper level support by Tuesday
night will rapidly diminish the flooding threat as storm coverage
and intensity also diminish. With some supply of Gulf moisture
continuing on Tuesday, the storms that form through the day will
still have enough punch to cause locally heavy rainfall. However,
the eastward progression of the front should allow this rain to
fall largely over areas that remain dry today/Sunday and Monday.
Antecedent dry conditions will preclude much of the flooding threat
by Tuesday, so only isolated flash flooding in urban and flood
prone areas is anticipated. The Marginal Risk is largely unchanged
from previous forecasts.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6LZ8i1DGnrnHmAHubfPiUy_Bha_2G_RP8Kgp0pOWxmpL= g8arBu_6BERdNtE-mwrkOLAqU5ufaxDBRD1p-sn1ObbN8pU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6LZ8i1DGnrnHmAHubfPiUy_Bha_2G_RP8Kgp0pOWxmpL= g8arBu_6BERdNtE-mwrkOLAqU5ufaxDBRD1p-sn1xCD5Xpw$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6LZ8i1DGnrnHmAHubfPiUy_Bha_2G_RP8Kgp0pOWxmpL= g8arBu_6BERdNtE-mwrkOLAqU5ufaxDBRD1p-sn1DnMwU0Q$=20

=3D =3D =3D
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FOUS30 KWBC 032326
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
626 PM EST Sun Nov 3 2024

Day 1
Valid 01Z Mon Nov 04 2024 - 12Z Mon Nov 04 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS AND THE OZARKS...

...Southern Plains and the Ozarks...
The axis of heaviest rainfall expected across Oklahoma and=20
Arkansas and southern Missouri tonight into early Monday morning.=20
A longwave trough over the Southwest is shifting eastward.=20
Embedded shortwave disturbances as well as a developing 90 kt jet=20
streak will move over the region through tonight. A well-=20
established low level jet (LLJ) will continue to advect plentiful=20
Gulf moisture northward into the area. The result will be training
bands of storms in OK/AR and into MO. Soils across OK, AR, into=20
southern Missouri have been saturating due to recent heavy rainfall.
This is likely to cause widely scattered to scattered instances of
flash flooding.

Given the plentiful moisture, training storms, saturating soils, and
some flood prone areas, the heavy rain could cause localized flash
flooding. The Ozarks remain in the highest risk area. The=20
topography will help to focus the heavy rainfall into the=20
valleys...which could result in rapid river, stream and creek=20
rises. This also locally increases the flash flooding threat as=20
compared to the same amount of rain falling over relatively flat=20
terrain. Flash flooding remains likely as amounts could locally=20
exceed 5 inches. Changes to the inherited risk areas were minor.


...Upper Midwest...
In the upper Midwest, the eastward shift in the guidance and a=20
more west to east movement of the expected convection should limit=20
how much instability and moisture reach the upper Mississippi=20
Valley. It's likely any remaining convection will be in a much=20
weakened state by the time the rain reaches this area. Since=20
similarly dry conditions and drought have impacted the upper Great=20
Lakes in recent weeks, the largely stratiform nature of the rain=20
should mean all of the rain will be beneficial with no flooding=20
concerns noted. Changes to the inherited risk area were minor.

Roth/Wegman


Day 2
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM NORTHEAST
TEXAS THROUGH PORTIONS OF WESTERN LOWER MICHIGAN...

20Z Update: Changes were few and far between for the D2 ERO with
the primary deviation being a slight shift eastward with the risk
areas given the latest trends within the forecast precip. A
secondary area of development over the course the evening into
tomorrow morning will generate another outflow dominant convective
pattern with a general expansion of the precip further to the north
and east leading to areas downstream in the Ozarks becoming the
benefactor of the heaviest precip. There's a strong consensus for
heavy rain totals exceeding 3" across the above area with a the 12z
HREF neighborhood probabilities exceeding 70% for the >3" threshold
extending from Southeast OK up through Northwest and North-Central
AR into Southeastern MO. EAS probabilities follow suit with an axis
of 50+% of >2" probs located over the same area with a 20-30% for

3" encompassing a good portion of the Ozarks. The antecedent

conditions leading in are relatively dry in the grand scheme with
the NASA SPoRT indicators leveling off the soil moisture
percentiles below 40% for much of the area anticipating heavy rain.
The more complex terrain does offer a slightly better risk than
typical compared to areas in the plains, so the prospects are
within the higher end of the SLGT risk margin, but just outside the
MDT risk upgrade for the time being. Pending the evolution of the
activity tonight, an upgrade may be necessary, targeting locations
likely centered over Northwest AR into Southern MO. Will continue
to monitor the situation closely as it evolves.

..Previous Forecast..

Few changes were made or needed to the Slight Risk area across the
middle of the country.

A deep longwave trough will continue move eastward but begin to
weaken and lift northward back into the jet stream on Monday. As it
does so, associated jet streaks will intensify downstream of the
trough, which will support its deamplification. The LLJ that has
been supplying Gulf moisture will also elongate towards the north
reaching as far north as lower Michigan by Monday. This will cause
the resultant moisture to focus in a SSW to NNE corridor from Texas
to Michigan. Unidirectional SSW flow will support training
thunderstorms. The strongest storms are expected from Texas through
Missouri, which will have access to the greatest Gulf instability
and moisture. The storms will gradually weaken the further north
you go, but are expected to maintain their integrity into Wisconsin
and Michigan. The topography of the Ozarks will further locally
enhance rainfall totals due to some upslope support.

Due to overlap with the rainfall footprint Monday with that
expected today, there is some potential for a Moderate Risk upgrade
from western Arkansas into southern Missouri. However, this will be
highly dependent on how much rain falls in that area today/Sunday.
Total rainfall amounts will be somewhat lower on Monday as compared
to Sunday, hence the importance of rain falling over the same areas
as Sunday to enhance the flooding threat to Moderate Risk levels. Thus,
the potential for an upgrade will continue to be evaluated.

Wegman

Day 3
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

20Z Update: Very minor adjustments were made to the MRGL risk
located across the Mississippi and Ohio Valleys as the overall
pattern and subsequent rainfall forecast maintained continuity from
run-to-run. Areal average QPF runs between 1-2" for the period with
the heaviest rainfall likely relegated over the Mid Mississippi
Valley Tuesday morning and afternoon before petering out as the
disturbance shifts eastward. Main threats will be relegated to
mainly urban and small stream flooding with more isolated flash
flood concerns in terms of an areal extent.

..Previous Forecast..

By Tuesday, a progressive cold front pushing across the Mississippi
Valley and associated upper level trough and shortwave will
separate...with the upper shortwave ejecting northeastward into the
Great Lakes, leaving the front behind. The combination of steady
forward movement of the storms through the day followed by the
rapid diminishing of any and all upper level support by Tuesday
night will rapidly diminish the flooding threat as storm coverage
and intensity also diminish. With some supply of Gulf moisture
continuing on Tuesday, the storms that form through the day will
still have enough punch to cause locally heavy rainfall. However,
the eastward progression of the front should allow this rain to
fall largely over areas that remain dry today/Sunday and Monday.
Antecedent dry conditions will preclude much of the flooding threat
by Tuesday, so only isolated flash flooding in urban and flood
prone areas is anticipated. The Marginal Risk is largely unchanged
from previous forecasts.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_5Zoof50v4Zi-zW6yZ96iaR1VCVa8jUi5CcW5X7e2hQo= 3IXlunDMjQ9N5UGuwkSyt0AzalrVp-TtyelR_5jip9bbkvU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_5Zoof50v4Zi-zW6yZ96iaR1VCVa8jUi5CcW5X7e2hQo= 3IXlunDMjQ9N5UGuwkSyt0AzalrVp-TtyelR_5jiJtlmiFA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_5Zoof50v4Zi-zW6yZ96iaR1VCVa8jUi5CcW5X7e2hQo= 3IXlunDMjQ9N5UGuwkSyt0AzalrVp-TtyelR_5ji2uHtX28$=20

=3D =3D =3D
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FOUS30 KWBC 040808
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
308 AM EST Mon Nov 4 2024

Day 1
Valid 12Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM EASTERN TEXAS
THROUGH WESTERN LOWER MICHIGAN...

...Changes...

Only a few modest changes were made to the inherited forecast.
There was a small southward nudge to the axis of heaviest rainfall
around Lake Michigan, so the Slight risk area was trimmed some in
Wisconsin and northern Lower Michigan in favor of a slightly
expanded Slight in eastern Illinois and far northwestern Indiana.
With some rain in portions of southeast Texas around Houston today,
the expectation of feeder cells into the main plume of moisture,
showers and storms further north warranted a small southward
extension of the Slight to near Houston.
A small Marginal risk was added to portions of east central New
Mexico.

...Texas to the Great Lakes...

A progressive trough over the Plains will continue tracking
eastward towards the Mississippi Valley today. Plentiful shortwave
energy and a strengthening southerly jet streak out ahead of the
trough will both work to increase forcing across the entire Slight
Risk area. The greatest lift and heaviest rainfall is expected from
far southeastern Oklahoma northeast to around St. Louis. Since this
area crosses the heart of the Ozarks, any upslope enhancement will
locally increase rainfall rates. The topography of the area may
also focus the flash flood potential in the valleys, further
increasing the risk of impacts. Plentiful Gulf moisture moving
north on a 40 kt LLJ will run into a developing surface low over
the Plains. As this moisture runs ahead of the NE-moving low the
combination of forcing and topography will enhance rainfall rates.
While there has been some rain in this area from eastern Oklahoma,
Arkansas, and southern Missouri, the heaviest rainfall amounts have
generally been west of where the heaviest rains are expected today.
This fact should mitigate the flood potential and impact somewhat.
Nonetheless, 2 days of heavy rain with rates to 3 inches per hour
in the strongest cells shows no signs of abating for today with all
the aforementioned ingredients still in place. The progressive
nature of the trough and resultant storms should also lessen the
flood risk just a little. Thus, the Slight Risk inherited for this
region continues to look good and no upgrades were considered. This
corridor is highlighted in an internal higher-end Slight.

Further south across Texas, there will be plentiful moisture but
the forcing will both be transient and largely missing this area.
Some rain fell today around Houston, so the threat is in the lower
end Slight range as any storms that form, while isolated to widely
scattered, will be capable of those higher end 3 inch per hour
rates, which especially over any flood prone urban areas could
cause flooding problems quickly.=20

Meanwhile further north towards Lake Michigan, plentiful forcing
will be in place but both instability and moisture amounts will be
decreasing with latitude. Thus, expect more stratiform rain across
this region...with much lower chances of the higher end rates. That
said, the rain should be longer duration than the heavier rain
further south, and for the Chicagoland area here too there will be
urban considerations which bump the risk level into the Slight
range.

...New Mexico...

A leeside low currently over south central New Mexico will track
northeast as several mesolows work to consolidate into a dominant
single low over Texas and Oklahoma late today. With peak heating,
some wraparound moisture and modest instability over an area with
modestly depressed FFG values, steady rain with some convective
cells ongoing over the area by this afternoon could result in an
isolated flash flooding threat, particularly over any burn scars or
other flood sensitive areas. Thus, a small Marginal Risk area was
added with this update. Precipitation will be ongoing further north
and into the mountains of southern Colorado but temperatures there
will be cold enough for most if not all of the precip to fall as
snow, precluding any flash flooding risk.

Wegman

Day 2
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

No changes were made to the inherited Marginal Risk area.

The upper level trough responsible for the past few days of heavy
rain across the southern and central Plains will finally retreat
back into the broader jet into Ontario and Quebec. The upper level
energy supporting the corridor of storms will continue supporting
storms across the Mississippi and Ohio Valleys Tuesday and into
Tuesday night respectively. As the energy lifts north, it will mark
the end of persistent heavy rain and storms from south to north.
Thus, the flooding threat will be more in the morning in Texas, and
more towards the night for the Ohio Valley. Training lines of
storms will move across the Mississippi Valley for much of the day.
These storms will be capable of heavy rains which may cause
isolated flash flooding, especially in any urban areas such as
Memphis. By Tuesday night, weakening of the storms and the shift
well away from any prior days' rain footprint will effectively end
the flooding threat.

Wegman

Day 3
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

Very few changes were needed to the inherited forecast.

Deep tropical moisture will have overspread all of Florida and will
be advancing into GA and SC at the start of the period Wednesday
morning. A lingering front over the Southeast may act as a focus
for convection across GA and SC as the deep tropical moisture moves
north into the front. Potential Tropical Cyclone Eighteen (PTC18)
is expected to move into the Gulf from Cuba and the northwest
Caribbean as well. For the Florida Peninsula, much of the flooding
threat will be determined by the eventual track of PTC18. The
latest guidance has kept the center of PTC18 far enough west over
the Gulf that despite shear pushing much of the rain associated
therewith to the eastern side of the circulation, it will still
largely remain offshore. However, with PWATs above 2.25 inches, it
won't take much for daily convection to produce heavy rainfall
almost anywhere in the state.=20

A bullseye of heavier rain is currently forecast across central GA
into SC. While the focus for the heavier rain will be the stalled
out front, there is considerable uncertainty as to instability,
which will greatly determine how strong any storms can get which
could cause flooding. For now it appears much of the rain in GA/SC
will be spread out through Wednesday and into Wednesday night,
which should easily be handled by the antecedent dry conditions.
Thus, the Marginal for this area remains in place with only minor
tweaks made. The area will continue to be monitored for a potential
Slight upgrade, which may not take much given the abundance of
tropical moisture any storms would have to work with.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4qtbO8hj28TThZLWSQDfBT1KPiZfOa2kvtbv6q8G9UvH= c-Gkd4NnnXqfIFnJYv7egAMRmJot_g4UqZ-MeFAzbqSU0io$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4qtbO8hj28TThZLWSQDfBT1KPiZfOa2kvtbv6q8G9UvH= c-Gkd4NnnXqfIFnJYv7egAMRmJot_g4UqZ-MeFAz3ktyRWg$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4qtbO8hj28TThZLWSQDfBT1KPiZfOa2kvtbv6q8G9UvH= c-Gkd4NnnXqfIFnJYv7egAMRmJot_g4UqZ-MeFAz3TbkrFQ$=20

=3D =3D =3D
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FOUS30 KWBC 041554
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1054 AM EST Mon Nov 4 2024

Day 1
Valid 16Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS SOUTHEAST
OKLAHOMA THROUGH THE OZARKS OF ARKANSAS AND MISSOURI...

...Texas to the Great Lakes...

16Z Update: Highly amplified flow ahead of a potent closed=20
low/upper trough axis moving through the Western CONUS will=20
continue to usher in well-above normal moisture anomalies from the=20
Gulf Coast up through the Great Lakes during the period. Heavy=20
rains overnight across OK into the AR/MO Ozarks have crashed FFG=20
indices regionally with cases of hourly FFG's now down <1"/hr=20
necessary to garner flash flood concerns. A widespread areal=20
average of 2-4" with locally as high as 7" has fallen over the=20
above area, saturating top layer soils up into the 70-85th=20
percentile as indicated via the latest NASA SPoRT output for the=20
0-10cm layer. Expectation is for the pattern to continue evolving=20
as such that another wave of heavy precip will initiate upstream=20
over OK as the nose of a 110kt 500mb jet streak rounds the base of=20
the mean trough over NM and ejects into the Southern Plains. Large=20
scale ascent will be maximized over within the time frame of 21z=20
through the remainder of the period allowing for a large cluster of
showers and storms to breakout and pivot east-northeast, aided by=20
the mean flow. A theta-E tongue is well documented over Eastern TX=20
through the Lower Mississippi Valley up through the the Missouri=20
Ozarks lending to favorable instability continuing through the=20
afternoon and evening time frames.=20

CAMs have become aggressive with the QPF output given the
aforementioned variables lending to a repeated pattern of heavy
rainfall over areas that saw copious amounts of rain overnight.
12z HREF signals a high end probability for at least 3" within the
neighborhood probability fields (70-90+%) for the Ozarks down into
the Southeast corner of OK and is correlated well with a 25-50% EAS
prob field for 3" with a max prob of 60% centered over South-
Central MO to the east of Springfield. HREF blended mean output is
elevated with 3-5" of rainfall over those areas with a max of up to
7", all of which is additional to what has transpired. Considering
the expected additional rainfall with rates generally 1-2"/hr at
peak intensity likely breaching the current FFG indicators for
1/3/6 hr periods, and in coordination with the TSA/LZK/SHV/SGF WFOs
impacted, a Moderate Risk ERO was introduced to cover that area
from Southeast OK up through North and Northwest AR into South-
Central MO.=20

Further south into TX, there is a growing consensus of heavy
thunderstorm genesis on the southern edge of the flanking line=20
along the axis of convergence settling within the western edge of=20
the theta-E gradient later this evening, mainly after the
development of the nocturnal LLJ. The jet streak on the base of=20
the mean trough under the closed low will be juxtaposed to the=20
northwest of Central TX allowing for increasing RER dynamics within
the confines of the I-35 corridor extending from DFW down into the
Austin/San Antonio metros. There is consensus on the development=20
of the flanking line, but exactly where the heaviest will occur=20
depends on the CAM output. Some place the heavy core of precip near
New Braunfels to San Antonio. Others place it near Austin to Waco.
Regardless, the instability fields will be prime for any=20
convective initiation with PWAT anomalies sufficiently above 2=20
deviations above normal. These types of setups are sneaky with=20
regards to potential, leading to an expansion of the SLGT risk to=20
include much of that I-35 corridor and adjacent areas in the Hill=20
Country to the west of the interstate.=20

Consensus for locally heavy rainfall north of the Missouri Valley
continues up into the Great Lakes as the low pressure progresses
into the Midwest with the amplified flow ahead of the potent
longwave trough. Lack of sufficient surface based instability caps
the potential for significant rainfall totals to more of 1-2" with
locally up to 3", but this would be enough to concern some urban
flash flood threats for those areas extending through Illinois into
Southeast WI into Western MI. The previous SLGT risk was maintained
as a result with a MRGL risk encompassing.=20

Kleebauer

...New Mexico...

16Z Update: Very little change necessary for the previous MRGL risk
over New Mexico as CAMs deviated very little from the overnight
output. Heaviest rainfall concerns will be located within that
northern periphery of the closed upper low pivoting eastward
through the area as ascent remains maximized within the diffluent
area north of the closed reflection, textbook synoptic scale
evolution. Higher terrain will actually resolve as snow, so the
main areas of concern will be the valleys and locales along the
I-40 corridor.=20

Kleebauer

..Previous Forecast..

A leeside low currently over south central New Mexico will track
northeast as several mesolows work to consolidate into a dominant
single low over Texas and Oklahoma late today. With peak heating,
some wraparound moisture and modest instability over an area with
modestly depressed FFG values, steady rain with some convective
cells ongoing over the area by this afternoon could result in an
isolated flash flooding threat, particularly over any burn scars or
other flood sensitive areas. Thus, a small Marginal Risk area was
added with this update. Precipitation will be ongoing further north
and into the mountains of southern Colorado but temperatures there
will be cold enough for most if not all of the precip to fall as
snow, precluding any flash flooding risk.

Wegman

Day 2
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

No changes were made to the inherited Marginal Risk area.

The upper level trough responsible for the past few days of heavy
rain across the southern and central Plains will finally retreat
back into the broader jet into Ontario and Quebec. The upper level
energy supporting the corridor of storms will continue supporting
storms across the Mississippi and Ohio Valleys Tuesday and into
Tuesday night respectively. As the energy lifts north, it will mark
the end of persistent heavy rain and storms from south to north.
Thus, the flooding threat will be more in the morning in Texas, and
more towards the night for the Ohio Valley. Training lines of
storms will move across the Mississippi Valley for much of the day.
These storms will be capable of heavy rains which may cause
isolated flash flooding, especially in any urban areas such as
Memphis. By Tuesday night, weakening of the storms and the shift
well away from any prior days' rain footprint will effectively end
the flooding threat.

Wegman

Day 3
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

Very few changes were needed to the inherited forecast.

Deep tropical moisture will have overspread all of Florida and will
be advancing into GA and SC at the start of the period Wednesday
morning. A lingering front over the Southeast may act as a focus
for convection across GA and SC as the deep tropical moisture moves
north into the front. Potential Tropical Cyclone Eighteen (PTC18)
is expected to move into the Gulf from Cuba and the northwest
Caribbean as well. For the Florida Peninsula, much of the flooding
threat will be determined by the eventual track of PTC18. The
latest guidance has kept the center of PTC18 far enough west over
the Gulf that despite shear pushing much of the rain associated
therewith to the eastern side of the circulation, it will still
largely remain offshore. However, with PWATs above 2.25 inches, it
won't take much for daily convection to produce heavy rainfall
almost anywhere in the state.

A bullseye of heavier rain is currently forecast across central GA
into SC. While the focus for the heavier rain will be the stalled
out front, there is considerable uncertainty as to instability,
which will greatly determine how strong any storms can get which
could cause flooding. For now it appears much of the rain in GA/SC
will be spread out through Wednesday and into Wednesday night,
which should easily be handled by the antecedent dry conditions.
Thus, the Marginal for this area remains in place with only minor
tweaks made. The area will continue to be monitored for a potential
Slight upgrade, which may not take much given the abundance of
tropical moisture any storms would have to work with.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4rsqJz5JQmuyOhOr-o08a_XA3ZM_En7YJfVLunnqBGNu= 0Q5ZlXVonjLFUna3nTiHS6oDLGE3S0Bc6ZZRN1F6hTAx4TY$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4rsqJz5JQmuyOhOr-o08a_XA3ZM_En7YJfVLunnqBGNu= 0Q5ZlXVonjLFUna3nTiHS6oDLGE3S0Bc6ZZRN1F6cSrVbjs$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4rsqJz5JQmuyOhOr-o08a_XA3ZM_En7YJfVLunnqBGNu= 0Q5ZlXVonjLFUna3nTiHS6oDLGE3S0Bc6ZZRN1F6gPCnVaM$=20

=3D =3D =3D
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FOUS30 KWBC 041953
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
253 PM EST Mon Nov 4 2024

Day 1
Valid 16Z Mon Nov 04 2024 - 12Z Tue Nov 05 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS SOUTHEAST
OKLAHOMA THROUGH THE OZARKS OF ARKANSAS AND MISSOURI...

...Texas to the Great Lakes...

16Z Update: Highly amplified flow ahead of a potent closed
low/upper trough axis moving through the Western CONUS will
continue to usher in well-above normal moisture anomalies from the
Gulf Coast up through the Great Lakes during the period. Heavy
rains overnight across OK into the AR/MO Ozarks have crashed FFG
indices regionally with cases of hourly FFG's now down <1"/hr
necessary to garner flash flood concerns. A widespread areal
average of 2-4" with locally as high as 7" has fallen over the
above area, saturating top layer soils up into the 70-85th
percentile as indicated via the latest NASA SPoRT output for the
0-10cm layer. Expectation is for the pattern to continue evolving
as such that another wave of heavy precip will initiate upstream
over OK as the nose of a 110kt 500mb jet streak rounds the base of
the mean trough over NM and ejects into the Southern Plains. Large
scale ascent will be maximized over within the time frame of 21z
through the remainder of the period allowing for a large cluster of
showers and storms to breakout and pivot east-northeast, aided by
the mean flow. A theta-E tongue is well documented over Eastern TX
through the Lower Mississippi Valley up through the the Missouri
Ozarks lending to favorable instability continuing through the
afternoon and evening time frames.

CAMs have become aggressive with the QPF output given the
aforementioned variables lending to a repeated pattern of heavy
rainfall over areas that saw copious amounts of rain overnight.
12z HREF signals a high end probability for at least 3" within the
neighborhood probability fields (70-90+%) for the Ozarks down into
the Southeast corner of OK and is correlated well with a 25-50% EAS
prob field for 3" with a max prob of 60% centered over South-
Central MO to the east of Springfield. HREF blended mean output is
elevated with 3-5" of rainfall over those areas with a max of up to
7", all of which is additional to what has transpired. Considering
the expected additional rainfall with rates generally 1-2"/hr at
peak intensity likely breaching the current FFG indicators for
1/3/6 hr periods, and in coordination with the TSA/LZK/SHV/SGF WFOs
impacted, a Moderate Risk ERO was introduced to cover that area
from Southeast OK up through North and Northwest AR into South-
Central MO.

Further south into TX, there is a growing consensus of heavy
thunderstorm genesis on the southern edge of the flanking line
along the axis of convergence settling within the western edge of
the theta-E gradient later this evening, mainly after the
development of the nocturnal LLJ. The jet streak on the base of
the mean trough under the closed low will be juxtaposed to the
northwest of Central TX allowing for increasing RER dynamics within
the confines of the I-35 corridor extending from DFW down into the
Austin/San Antonio metros. There is consensus on the development
of the flanking line, but exactly where the heaviest will occur
depends on the CAM output. Some place the heavy core of precip near
New Braunfels to San Antonio. Others place it near Austin to Waco.
Regardless, the instability fields will be prime for any
convective initiation with PWAT anomalies sufficiently above 2
deviations above normal. These types of setups are sneaky with
regards to potential, leading to an expansion of the SLGT risk to
include much of that I-35 corridor and adjacent areas in the Hill
Country to the west of the interstate.

Consensus for locally heavy rainfall north of the Missouri Valley
continues up into the Great Lakes as the low pressure progresses
into the Midwest with the amplified flow ahead of the potent
longwave trough. Lack of sufficient surface based instability caps
the potential for significant rainfall totals to more of 1-2" with
locally up to 3", but this would be enough to concern some urban
flash flood threats for those areas extending through Illinois into
Southeast WI into Western MI. The previous SLGT risk was maintained
as a result with a MRGL risk encompassing.

Kleebauer

...New Mexico...

16Z Update: Very little change necessary for the previous MRGL risk
over New Mexico as CAMs deviated very little from the overnight
output. Heaviest rainfall concerns will be located within that
northern periphery of the closed upper low pivoting eastward
through the area as ascent remains maximized within the diffluent
area north of the closed reflection, textbook synoptic scale
evolution. Higher terrain will actually resolve as snow, so the
main areas of concern will be the valleys and locales along the
I-40 corridor.

Kleebauer

..Previous Forecast..

A leeside low currently over south central New Mexico will track
northeast as several mesolows work to consolidate into a dominant
single low over Texas and Oklahoma late today. With peak heating,
some wraparound moisture and modest instability over an area with
modestly depressed FFG values, steady rain with some convective
cells ongoing over the area by this afternoon could result in an
isolated flash flooding threat, particularly over any burn scars or
other flood sensitive areas. Thus, a small Marginal Risk area was
added with this update. Precipitation will be ongoing further north
and into the mountains of southern Colorado but temperatures there
will be cold enough for most if not all of the precip to fall as
snow, precluding any flash flooding risk.

Wegman

Day 2
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

20Z Update: The previous MRGL risk was relatively maintained as the
overall synoptic pattern if forecast to decay somewhat, limiting
the magnitude of heavy rainfall with regards to both rates and
totals. A core of heavy rainfall is still anticipated, but the
limiting factor of rates generally 1-1.5"/hr at peak intensity over
an area that has seen very little rainfall for close to a month
will inhibit significant flash flood concerns and relegate the
setup to more of the isolated flash flood variety. The current
ensemble means indicate the heaviest QPF footprint within the
confines of the Lower to Mid-Mississippi Valley inflection areas
encompassing Northeastern AR through Southeast MO and Western TN.
Some of the CAMs are a bit bullish over areas like Memphis which
could garner some flash flood interest even with the lower rates
just due to the urbanization factors. Even still, FFG markers for
the 1-hour time frame are running between 2.5-3"/hr over the area,
so the threat will be mainly within the MRGL threshold and perhaps
just missing out on the Slight Risk prospects with the dry
antecedent conditions being the deciding factor. ARI exceedance
probabilities are pretty tame with a 5-10% output within the latest
HREF. This isn't exactly one that moves the needle to an upgrade,
in agreement with the impacted WFO's. As a result, only minor=20
adjustments were made to expand the risk area a touch further west=20
and north, and to nudge a bit more in the Southeast flank as=20
convective activity is likely over areas near Baton Rouge and=20
points west.=20

Kleebauer

..Previous Forecast..=20

The upper level trough responsible for the past few days of heavy
rain across the southern and central Plains will finally retreat
back into the broader jet into Ontario and Quebec. The upper level
energy supporting the corridor of storms will continue supporting
storms across the Mississippi and Ohio Valleys Tuesday and into
Tuesday night respectively. As the energy lifts north, it will mark
the end of persistent heavy rain and storms from south to north.
Thus, the flooding threat will be more in the morning in Texas, and
more towards the night for the Ohio Valley. Training lines of
storms will move across the Mississippi Valley for much of the day.
These storms will be capable of heavy rains which may cause
isolated flash flooding, especially in any urban areas such as
Memphis. By Tuesday night, weakening of the storms and the shift
well away from any prior days' rain footprint will effectively end
the flooding threat.

Wegman

Day 3
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR CENTRAL AND
EASTERN GEORGIA INTO PORTIONS OF WESTERN SOUTH CAROLINA...

20z Update: Guidance continues to trend upwards with regards to the
evolving heavy rain forecast across GA into the Western portions of
SC for Wednesday. Deep tropical moisture advection will funnel out
ahead of now Tropical Depression 18 (TD18), which will be a
hurricane likely by the time of this forecast evolution. The
moisture flux is caused by the proxy of the disturbance within the
western fringes of a broad surface ridge located over the Western
Atlantic providing a "highway" for the enhanced tropical moisture
plume to funnel northward into parts of the Southeastern U.S. To
the west, our longwave trough and closed low pattern will become
sheared out with the cold front slowing and eventually becoming a quasi-stationary boundary once it enters the Ohio and Tennessee=20
Valleys. A 130kt jet streak will be located over the Great Lakes=20
into the Northeastern U.S providing a broad upper forcing pattern=20
to transpire within the RER of the jet. This will help in=20
initiation of precip across parts of GA into SC with some modest=20
rainfall developing.=20

As we work into Wednesday evening the boundary to the north will
slowly drift into the Southeast with a developing convergence axis
located over Central and Eastern GA into parts of the SC Piedmont
leading to a broadening axis of steady precip with some increasing
convective elements thanks to the unstable airmass that is
advecting into the area. Several members of the global ensemble
suite along with the bias corrected ensemble forecast indicate a
substantial area of rainfall with totals >4" becoming focused
within the greatest convergence axis along the slow frontal
progression. With the high pressure stable in the Atlantic, a
persistent easterly component to the wind field will only add to
the convergence regime providing a prime focal point for slow-
moving convection over the course of the overnight hours through
Thursday morning. This setup can be characterized as a Predecessor
Rainfall Event (PRE) that can develop well out ahead of an
approaching tropical disturbance as it moves closer to CONUS. The
key in all this is the tropical moisture advection that enhances
the environment for more effective warm rain processes that aren't
common within more mid-latitude cyclones and patterns. The
interaction of the front and surface ridging will make all the
difference on the specific locations that see the most rainfall. In
this case, there's a growing consensus over Central and Eastern GA
extending to the GA/SC line near Augusta.=20

Considering the variables at play and the trend towards a more
prolific rainfall event, a Slight Risk was introduced across the
areas above with a MRGL risk extending through portions of the
Southeast, including Florida where the proximity to the tropical
disturbance will allow for some heavier convective prospects over
the Peninsula. There is still some uncertainty on the exact
location of the heaviest precip and PRE setup, so be sure to
monitor the situation closely as the location of the higher risk
could change, as well as an upgrade to a higher risk if the signal
maintains magnitude and/or higher confidence in the potential.

Kleebauer

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6juNROXd3QOzlWNvKSYwIEU1cas0NltOfGffodxj6oiL= 5XlDBpIDUCxPqPTSLVX7BnnXHkIw0IL7TkaTnqNyq6Y8Ugs$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6juNROXd3QOzlWNvKSYwIEU1cas0NltOfGffodxj6oiL= 5XlDBpIDUCxPqPTSLVX7BnnXHkIw0IL7TkaTnqNysafem4Y$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6juNROXd3QOzlWNvKSYwIEU1cas0NltOfGffodxj6oiL= 5XlDBpIDUCxPqPTSLVX7BnnXHkIw0IL7TkaTnqNyuAXeZqk$=20

=3D =3D =3D
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FOUS30 KWBC 050055
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
755 PM EST Mon Nov 4 2024

Day 1
Valid 01Z Tue Nov 05 2024 - 12Z Tue Nov 05 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS SOUTHEAST
OKLAHOMA THROUGH THE OZARKS OF ARKANSAS AND MISSOURI...

...01z Update...

Little change needed with this update, as the Moderate Risk area
remains on track with HRRR runs consistently depicting the risk for
additional localized 5"+ totals centered over northwest AR through
12z (coincident with the 18z HREF 40-km neighborhood probabilities
for 5" exceedance of 15-25%). More numerous totals of 2-4" are=20
expected across the Moderate Risk area (where FFGs generally range=20
from 1.5-2.5"). Other than trimming the back-end of the risk areas=20
(where the threat has ended), only minor adjustments were necessary.

Churchill


...Previous Discussion...

...Texas to the Great Lakes...

Highly amplified flow ahead of a potent closed low/upper trough=20
axis moving through the Western CONUS will continue to usher in=20
well-above normal moisture anomalies from the Gulf Coast up through
the Great Lakes during the period. Heavy rains overnight across OK
into the AR/MO Ozarks have crashed FFG indices regionally with=20
cases of hourly FFG's now down <1"/hr necessary to garner flash=20
flood concerns. A widespread areal average of 2-4" with locally as=20
high as 7" has fallen over the above area, saturating top layer=20
soils up into the 70-85th percentile as indicated via the latest=20
NASA SPoRT output for the 0-10cm layer. Expectation is for the=20
pattern to continue evolving as such that another wave of heavy=20
precip will initiate upstream over OK as the nose of a 110kt 500mb=20
jet streak rounds the base of the mean trough over NM and ejects=20
into the Southern Plains. Large scale ascent will be maximized over
within the time frame of 21z through the remainder of the period=20
allowing for a large cluster of showers and storms to breakout and=20
pivot east-northeast, aided by the mean flow. A theta-E tongue is=20
well documented over Eastern TX through the Lower Mississippi=20
Valley up through the the Missouri Ozarks lending to favorable=20
instability continuing through the afternoon and evening time=20
frames.

CAMs have become aggressive with the QPF output given the
aforementioned variables lending to a repeated pattern of heavy
rainfall over areas that saw copious amounts of rain overnight.
12z HREF signals a high end probability for at least 3" within the
neighborhood probability fields (70-90+%) for the Ozarks down into
the Southeast corner of OK and is correlated well with a 25-50% EAS
prob field for 3" with a max prob of 60% centered over South-
Central MO to the east of Springfield. HREF blended mean output is
elevated with 3-5" of rainfall over those areas with a max of up to
7", all of which is additional to what has transpired. Considering
the expected additional rainfall with rates generally 1-2"/hr at
peak intensity likely breaching the current FFG indicators for
1/3/6 hr periods, and in coordination with the TSA/LZK/SHV/SGF WFOs
impacted, a Moderate Risk ERO was introduced to cover that area
from Southeast OK up through North and Northwest AR into South-
Central MO.

Further south into TX, there is a growing consensus of heavy
thunderstorm genesis on the southern edge of the flanking line
along the axis of convergence settling within the western edge of
the theta-E gradient later this evening, mainly after the
development of the nocturnal LLJ. The jet streak on the base of
the mean trough under the closed low will be juxtaposed to the
northwest of Central TX allowing for increasing RER dynamics within
the confines of the I-35 corridor extending from DFW down into the
Austin/San Antonio metros. There is consensus on the development
of the flanking line, but exactly where the heaviest will occur
depends on the CAM output. Some place the heavy core of precip near
New Braunfels to San Antonio. Others place it near Austin to Waco.
Regardless, the instability fields will be prime for any
convective initiation with PWAT anomalies sufficiently above 2
deviations above normal. These types of setups are sneaky with
regards to potential, leading to an expansion of the SLGT risk to
include much of that I-35 corridor and adjacent areas in the Hill
Country to the west of the interstate.

Consensus for locally heavy rainfall north of the Missouri Valley
continues up into the Great Lakes as the low pressure progresses
into the Midwest with the amplified flow ahead of the potent
longwave trough. Lack of sufficient surface based instability caps
the potential for significant rainfall totals to more of 1-2" with
locally up to 3", but this would be enough to concern some urban
flash flood threats for those areas extending through Illinois into
Southeast WI into Western MI. The previous SLGT risk was maintained
as a result with a MRGL risk encompassing.

Kleebauer


Day 2
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MISSISSIPPI AND OHIO VALLEYS...

20Z Update: The previous MRGL risk was relatively maintained as the
overall synoptic pattern if forecast to decay somewhat, limiting
the magnitude of heavy rainfall with regards to both rates and
totals. A core of heavy rainfall is still anticipated, but the
limiting factor of rates generally 1-1.5"/hr at peak intensity over
an area that has seen very little rainfall for close to a month
will inhibit significant flash flood concerns and relegate the
setup to more of the isolated flash flood variety. The current
ensemble means indicate the heaviest QPF footprint within the
confines of the Lower to Mid-Mississippi Valley inflection areas
encompassing Northeastern AR through Southeast MO and Western TN.
Some of the CAMs are a bit bullish over areas like Memphis which
could garner some flash flood interest even with the lower rates
just due to the urbanization factors. Even still, FFG markers for
the 1-hour time frame are running between 2.5-3"/hr over the area,
so the threat will be mainly within the MRGL threshold and perhaps
just missing out on the Slight Risk prospects with the dry
antecedent conditions being the deciding factor. ARI exceedance
probabilities are pretty tame with a 5-10% output within the latest
HREF. This isn't exactly one that moves the needle to an upgrade,
in agreement with the impacted WFO's. As a result, only minor
adjustments were made to expand the risk area a touch further west
and north, and to nudge a bit more in the Southeast flank as
convective activity is likely over areas near Baton Rouge and
points west.

Kleebauer

..Previous Forecast..

The upper level trough responsible for the past few days of heavy
rain across the southern and central Plains will finally retreat
back into the broader jet into Ontario and Quebec. The upper level
energy supporting the corridor of storms will continue supporting
storms across the Mississippi and Ohio Valleys Tuesday and into
Tuesday night respectively. As the energy lifts north, it will mark
the end of persistent heavy rain and storms from south to north.
Thus, the flooding threat will be more in the morning in Texas, and
more towards the night for the Ohio Valley. Training lines of
storms will move across the Mississippi Valley for much of the day.
These storms will be capable of heavy rains which may cause
isolated flash flooding, especially in any urban areas such as
Memphis. By Tuesday night, weakening of the storms and the shift
well away from any prior days' rain footprint will effectively end
the flooding threat.

Wegman


Day 3
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR CENTRAL AND
EASTERN GEORGIA INTO PORTIONS OF WESTERN SOUTH CAROLINA...

20z Update: Guidance continues to trend upwards with regards to the
evolving heavy rain forecast across GA into the Western portions of
SC for Wednesday. Deep tropical moisture advection will funnel out
ahead of now Tropical Depression 18 (TD18), which will be a
hurricane likely by the time of this forecast evolution. The
moisture flux is caused by the proxy of the disturbance within the
western fringes of a broad surface ridge located over the Western
Atlantic providing a "highway" for the enhanced tropical moisture
plume to funnel northward into parts of the Southeastern U.S. To
the west, our longwave trough and closed low pattern will become
sheared out with the cold front slowing and eventually becoming a quasi-stationary boundary once it enters the Ohio and Tennessee
Valleys. A 130kt jet streak will be located over the Great Lakes
into the Northeastern U.S providing a broad upper forcing pattern
to transpire within the RER of the jet. This will help in
initiation of precip across parts of GA into SC with some modest
rainfall developing.

As we work into Wednesday evening the boundary to the north will
slowly drift into the Southeast with a developing convergence axis
located over Central and Eastern GA into parts of the SC Piedmont
leading to a broadening axis of steady precip with some increasing
convective elements thanks to the unstable airmass that is
advecting into the area. Several members of the global ensemble
suite along with the bias corrected ensemble forecast indicate a
substantial area of rainfall with totals >4" becoming focused
within the greatest convergence axis along the slow frontal
progression. With the high pressure stable in the Atlantic, a
persistent easterly component to the wind field will only add to
the convergence regime providing a prime focal point for slow-
moving convection over the course of the overnight hours through
Thursday morning. This setup can be characterized as a Predecessor
Rainfall Event (PRE) that can develop well out ahead of an
approaching tropical disturbance as it moves closer to CONUS. The
key in all this is the tropical moisture advection that enhances
the environment for more effective warm rain processes that aren't
common within more mid-latitude cyclones and patterns. The
interaction of the front and surface ridging will make all the
difference on the specific locations that see the most rainfall. In
this case, there's a growing consensus over Central and Eastern GA
extending to the GA/SC line near Augusta.

Considering the variables at play and the trend towards a more
prolific rainfall event, a Slight Risk was introduced across the
areas above with a MRGL risk extending through portions of the
Southeast, including Florida where the proximity to the tropical
disturbance will allow for some heavier convective prospects over
the Peninsula. There is still some uncertainty on the exact
location of the heaviest precip and PRE setup, so be sure to
monitor the situation closely as the location of the higher risk
could change, as well as an upgrade to a higher risk if the signal
maintains magnitude and/or higher confidence in the potential.

Kleebauer


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4echjguSa-36PJeqITqnlKnCIECgDq3gVeA9GK0KyIpY= rZv7v0Yi4LZAAtzI2z75Z4EzyXzvgH1vtB5hDjhmQP73Ny8$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4echjguSa-36PJeqITqnlKnCIECgDq3gVeA9GK0KyIpY= rZv7v0Yi4LZAAtzI2z75Z4EzyXzvgH1vtB5hDjhmVHfP--8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4echjguSa-36PJeqITqnlKnCIECgDq3gVeA9GK0KyIpY= rZv7v0Yi4LZAAtzI2z75Z4EzyXzvgH1vtB5hDjhmp05aWx8$=20

=3D =3D =3D
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FOUS30 KWBC 050824
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
324 AM EST Tue Nov 5 2024

Day 1
Valid 12Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER TO MID MISSISSIPPI AND LOWER OHIO VALLEYS...

A cold front tracking east across the middle of the country is
expected to stall out generally along the Mississippi and Ohio
Rivers late tonight. Southerly flow off the Gulf will continue
pumping plentiful moisture into the front. Meanwhile, in the upper
levels, a large longwave trough over the west will establish itself
as a positively tilted trough by tonight as it digs southwestward
over the Southwest. Before it does so, the last potent shortwave of
the "old" trough will race northeastward into the Great Lakes as
the leading edge of the trough becomes a roughly straight line
southwesterly from the Southwest right through into eastern=20
Canada.

The potent shortwave and associated surface low will both race
northeastward through the period. While they're over the upper
Mississippi Valley, they will move the front currently stalled from
Texas through Michigan eastward a bit to align with the Slight and
Marginal Risk areas along the Mississippi and Ohio Rivers. This
will give the hard hit northwestern Arkansas region a break as the
heaviest rain shifts east. However, by tonight, both features will
be well into the Great Lakes and Canada, so the forcing pushing
them east will quickly diminish, resulting in another stall-out of
the front. With continuous Gulf moisture, another round of training thunderstorms is expected up the Mississippi and lower Ohio Rivers
tonight. Given both the prior history of this front stalling as
well as urban concerns in the Memphis area especially, a Slight
Risk area was introduced with this update.=20

Despite the stalled out front keeping the rainfall largely confined
to a narrow corridor, the upper level forcing quickly weakening
tonight should hold rates and coverage in check much better tonight
as compared to the ongoing storms over Texas, Arkansas and Missouri
right now. Thus, forecast rainfall amounts are considerably lower
today and tonight than yesterday. The Slight is considered a
"lower-end Slight" with any flash flooding impacts expected to be
largely confined to low-lying flood prone areas and urban areas.
Like areas further west, this area has also been very dry prior to
this rainfall, so it will still take a prolonged period of heavy
rainfall to result in flash flooding.

Wegman

Day 2
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
GEORGIA AND SOUTH CAROLINA...

A large plume of deep tropical moisture will overspread all of
Florida and move into Georgia and South Carolina on Wednesday and
Wednesday night. This same plume is home to T.S. Rafael down in the
Caribbean. PWATs will increase to as high as 2.25 inches, meaning
the storms expected to form will have plenty of moisture to convert
to heavy rainfall. The front over the Ohio Valley is unlikely to
play too much of a role in the storms over Georgia and South
Carolina. Rather, the guidance suggests a secondary front will from
at the leading edge of the moisture plume that will likely be
enhanced by the right entrance region of the upper level jet=20
streak, as well as possibly some upslope component (especially in=20
South Carolina). Regardless of the primary lifting mechanism, there
is good agreement in the guidance for an area of 3 to 5 inches of
rain (though likely much higher amounts will be embedded) in the
Slight Risk area, which is a small increase in amounts from the
previous forecast.

As with areas further west the past several days, this area has
also been incredibly dry lately, with many areas not having seen
appreciable rain in a month. For the swampy and sandy areas, this
will mean it will take a lot of rain before runoff converts to
flooding. Further north across interior SC and GA, the clay soils
are likely quite hydrophobic due to the recent dry weather, which
will notably increase runoff once the heavy rain gets started.
Thus, locally increased impacts are possible. An internal higher-
end Slight area was introduced for the peak rainfall area of east-
central Georgia and west central South Carolina for this potential.

Since this plume is home to T.S. Rafael, this would be considered a
predecessor rain event (PRE) if Rafael were to head towards the Big
Bend and GA/SC. However, since the latest forecasts keep Rafael
tracking westward in the Gulf this rainfall event is not considered
a PRE.=20

Wegman

Day 3
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST AS WELL AS FOR PORTIONS OF THE SOUTHERN PLAINS...

...Southeast...

The cold front over the Appalachians that will drive the Day
2/Wednesday rainfall event will move southward to coastal South
Carolina and southern Georgia Thursday and Thursday night. The
southerly flow of deep tropical moisture ahead of the front will
abate somewhat in favor of a more neutral easterly flow. This will
keep periods of heavy rain going...but both less widespread, less
persistent, and less heavily. The core of heaviest rain will shift
to the coast of SC/GA and north FL, but since most of this area is
likely to not have seen substantive amounts of rain on Wednesday,
and the coastal swamps can usually handle a lot of rainfall with
few problems, have opted to keep the area in a Marginal Risk for
this update. However, recent model trends have been for the
heaviest rain to increase with time as the CAMs move into this
period of time. Should that happen a Slight Risk will likely be
necessary.

...Southern Plains...

A potent upper level low will begin to eject out of the Southwest
and into the southern Plains on Thursday. A strong cold front will
develop as a result with plentiful snow into much of northeastern
New Mexico. This area was trimmed from the Marginal Risk with this
update. For the rest of the Marginal Risk area, some Gulf moisture
will be captured and advected northward across north Texas and
Oklahoma, but amounts will be somewhat limited. With only broad
forcing from an upper level jet streak but few coherent features
away from the strong cold front, the rainfall footprint will be
broad and disorganized. This area has seen plentiful rainfall over
the past few days, so the additional rainfall, while not much, may
still cause isolated instances of flash flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6et4exlJfBDFxb0X8QtSsYBQfNjpfZiwWztCcwlqLvUc= gc9M1whR3w9v4X5_sTxiXb8bHnpU198Ml3BK1EvP88AtxYc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6et4exlJfBDFxb0X8QtSsYBQfNjpfZiwWztCcwlqLvUc= gc9M1whR3w9v4X5_sTxiXb8bHnpU198Ml3BK1EvPVNoiOpA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6et4exlJfBDFxb0X8QtSsYBQfNjpfZiwWztCcwlqLvUc= gc9M1whR3w9v4X5_sTxiXb8bHnpU198Ml3BK1EvPkF6VaV0$=20

=3D =3D =3D
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FOUS30 KWBC 051542
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1042 AM EST Tue Nov 5 2024

Day 1
Valid 16Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER TO MID MISSISSIPPI AND LOWER OHIO VALLEYS...

1600Z Update...

Overall, modest changes made for the late-morning update to=20
account for the latest 12Z HREF guidance and recent HRRR trends.=20
There has been some overall tightening of the QPF gradient from the
lower MS Valley up into the lower OH Valley for the late-day and=20
overnight hours, but still a threat for a ribbon of locally heavy=20
rainfall totals. This will include areas from northwest MS through=20
western TN and western KY where the latest guidance still supports=20
a 40 to 45 kt southerly low-level jet ahead of the cold front=20
approaching the area, and thus a channel of rather strong moisture=20 transport. Instability though is overall expected to rather modest=20
and this will likely tend to cut down on the rainfall rates of the=20
areal shower and thunderstorm activity. Nevertheless, there may be=20
some localized training of the convection this evening, especially=20
in the 00Z to 06Z time period, and a few pockets of 2 to 3 inch=20
rainfall totals will be possible.

Based on this, the Slight Risk area has been maintained although=20
adjusted just slightly off to the east and trimmed in areal extent
to account for the 12Z HREF consensus. Given the eastward advance=20
of the overall rainfall shield currently over the lower/middle MS=20
Valley and southeast TX, the western portion of the Marginal Risk=20
area has been trimmed away.

Orrison


Previous Discussion...

A cold front tracking east across the middle of the country is=20
expected to stall out generally along the Mississippi and Ohio=20
Rivers late tonight. Southerly flow off the Gulf will continue=20
pumping plentiful moisture into the front. Meanwhile, in the upper=20
levels, a large longwave trough over the west will establish itself
as a positively tilted trough by tonight as it digs southwestward=20
over the Southwest. Before it does so, the last potent shortwave of
the "old" trough will race northeastward into the Great Lakes as=20
the leading edge of the trough becomes a roughly straight line=20
southwesterly from the Southwest right through into eastern Canada.

The potent shortwave and associated surface low will both race
northeastward through the period. While they're over the upper
Mississippi Valley, they will move the front currently stalled from
Texas through Michigan eastward a bit to align with the Slight and
Marginal Risk areas along the Mississippi and Ohio Rivers. This
will give the hard hit northwestern Arkansas region a break as the
heaviest rain shifts east. However, by tonight, both features will
be well into the Great Lakes and Canada, so the forcing pushing
them east will quickly diminish, resulting in another stall-out of
the front. With continuous Gulf moisture, another round of training thunderstorms is expected up the Mississippi and lower Ohio Rivers
tonight. Given both the prior history of this front stalling as
well as urban concerns in the Memphis area especially, a Slight
Risk area was introduced with this update.

Despite the stalled out front keeping the rainfall largely confined
to a narrow corridor, the upper level forcing quickly weakening
tonight should hold rates and coverage in check much better tonight
as compared to the ongoing storms over Texas, Arkansas and Missouri
right now. Thus, forecast rainfall amounts are considerably lower
today and tonight than yesterday. The Slight is considered a
"lower-end Slight" with any flash flooding impacts expected to be
largely confined to low-lying flood prone areas and urban areas.
Like areas further west, this area has also been very dry prior to
this rainfall, so it will still take a prolonged period of heavy
rainfall to result in flash flooding.

Wegman

Day 2
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
GEORGIA AND SOUTH CAROLINA...

A large plume of deep tropical moisture will overspread all of
Florida and move into Georgia and South Carolina on Wednesday and
Wednesday night. This same plume is home to T.S. Rafael down in the
Caribbean. PWATs will increase to as high as 2.25 inches, meaning
the storms expected to form will have plenty of moisture to convert
to heavy rainfall. The front over the Ohio Valley is unlikely to
play too much of a role in the storms over Georgia and South
Carolina. Rather, the guidance suggests a secondary front will from
at the leading edge of the moisture plume that will likely be
enhanced by the right entrance region of the upper level jet
streak, as well as possibly some upslope component (especially in
South Carolina). Regardless of the primary lifting mechanism, there
is good agreement in the guidance for an area of 3 to 5 inches of
rain (though likely much higher amounts will be embedded) in the
Slight Risk area, which is a small increase in amounts from the
previous forecast.

As with areas further west the past several days, this area has
also been incredibly dry lately, with many areas not having seen
appreciable rain in a month. For the swampy and sandy areas, this
will mean it will take a lot of rain before runoff converts to
flooding. Further north across interior SC and GA, the clay soils
are likely quite hydrophobic due to the recent dry weather, which
will notably increase runoff once the heavy rain gets started.
Thus, locally increased impacts are possible. An internal higher-
end Slight area was introduced for the peak rainfall area of east-
central Georgia and west central South Carolina for this potential.

Since this plume is home to T.S. Rafael, this would be considered a
predecessor rain event (PRE) if Rafael were to head towards the Big
Bend and GA/SC. However, since the latest forecasts keep Rafael
tracking westward in the Gulf this rainfall event is not considered
a PRE.

Wegman

Day 3
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST AS WELL AS FOR PORTIONS OF THE SOUTHERN PLAINS...

...Southeast...

The cold front over the Appalachians that will drive the Day
2/Wednesday rainfall event will move southward to coastal South
Carolina and southern Georgia Thursday and Thursday night. The
southerly flow of deep tropical moisture ahead of the front will
abate somewhat in favor of a more neutral easterly flow. This will
keep periods of heavy rain going...but both less widespread, less
persistent, and less heavily. The core of heaviest rain will shift
to the coast of SC/GA and north FL, but since most of this area is
likely to not have seen substantive amounts of rain on Wednesday,
and the coastal swamps can usually handle a lot of rainfall with
few problems, have opted to keep the area in a Marginal Risk for
this update. However, recent model trends have been for the
heaviest rain to increase with time as the CAMs move into this
period of time. Should that happen a Slight Risk will likely be
necessary.

...Southern Plains...

A potent upper level low will begin to eject out of the Southwest
and into the southern Plains on Thursday. A strong cold front will
develop as a result with plentiful snow into much of northeastern
New Mexico. This area was trimmed from the Marginal Risk with this
update. For the rest of the Marginal Risk area, some Gulf moisture
will be captured and advected northward across north Texas and
Oklahoma, but amounts will be somewhat limited. With only broad
forcing from an upper level jet streak but few coherent features
away from the strong cold front, the rainfall footprint will be
broad and disorganized. This area has seen plentiful rainfall over
the past few days, so the additional rainfall, while not much, may
still cause isolated instances of flash flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!78p9zQSmpT4dFwo10Vc2c_4MIz9XH57Ot_F61efhaFMw= 6C4VzxceSmvg79SuVcBWBnrh6HoGrDW93nAfDn8PzSGXJwU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!78p9zQSmpT4dFwo10Vc2c_4MIz9XH57Ot_F61efhaFMw= 6C4VzxceSmvg79SuVcBWBnrh6HoGrDW93nAfDn8PZ8Gdas8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!78p9zQSmpT4dFwo10Vc2c_4MIz9XH57Ot_F61efhaFMw= 6C4VzxceSmvg79SuVcBWBnrh6HoGrDW93nAfDn8PGu2h2Eo$=20

=3D =3D =3D
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FOUS30 KWBC 051949
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
249 PM EST Tue Nov 5 2024

Day 1
Valid 16Z Tue Nov 05 2024 - 12Z Wed Nov 06 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER TO MID MISSISSIPPI AND LOWER OHIO VALLEYS...

1600Z Update...

Overall, modest changes made for the late-morning update to
account for the latest 12Z HREF guidance and recent HRRR trends.
There has been some overall tightening of the QPF gradient from the
lower MS Valley up into the lower OH Valley for the late-day and
overnight hours, but still a threat for a ribbon of locally heavy
rainfall totals. This will include areas from northwest MS through
western TN and western KY where the latest guidance still supports
a 40 to 45 kt southerly low-level jet ahead of the cold front
approaching the area, and thus a channel of rather strong moisture
transport. Instability though is overall expected to rather modest
and this will likely tend to cut down on the rainfall rates of the
areal shower and thunderstorm activity. Nevertheless, there may be
some localized training of the convection this evening, especially
in the 00Z to 06Z time period, and a few pockets of 2 to 3 inch
rainfall totals will be possible.

Based on this, the Slight Risk area has been maintained although
adjusted just slightly off to the east and trimmed in areal extent
to account for the 12Z HREF consensus. Given the eastward advance
of the overall rainfall shield currently over the lower/middle MS
Valley and southeast TX, the western portion of the Marginal Risk
area has been trimmed away.

Orrison


Previous Discussion...

A cold front tracking east across the middle of the country is
expected to stall out generally along the Mississippi and Ohio
Rivers late tonight. Southerly flow off the Gulf will continue
pumping plentiful moisture into the front. Meanwhile, in the upper
levels, a large longwave trough over the west will establish itself
as a positively tilted trough by tonight as it digs southwestward
over the Southwest. Before it does so, the last potent shortwave of
the "old" trough will race northeastward into the Great Lakes as
the leading edge of the trough becomes a roughly straight line
southwesterly from the Southwest right through into eastern Canada.

The potent shortwave and associated surface low will both race
northeastward through the period. While they're over the upper
Mississippi Valley, they will move the front currently stalled from
Texas through Michigan eastward a bit to align with the Slight and
Marginal Risk areas along the Mississippi and Ohio Rivers. This
will give the hard hit northwestern Arkansas region a break as the
heaviest rain shifts east. However, by tonight, both features will
be well into the Great Lakes and Canada, so the forcing pushing
them east will quickly diminish, resulting in another stall-out of
the front. With continuous Gulf moisture, another round of training thunderstorms is expected up the Mississippi and lower Ohio Rivers
tonight. Given both the prior history of this front stalling as
well as urban concerns in the Memphis area especially, a Slight
Risk area was introduced with this update.

Despite the stalled out front keeping the rainfall largely confined
to a narrow corridor, the upper level forcing quickly weakening
tonight should hold rates and coverage in check much better tonight
as compared to the ongoing storms over Texas, Arkansas and Missouri
right now. Thus, forecast rainfall amounts are considerably lower
today and tonight than yesterday. The Slight is considered a
"lower-end Slight" with any flash flooding impacts expected to be
largely confined to low-lying flood prone areas and urban areas.
Like areas further west, this area has also been very dry prior to
this rainfall, so it will still take a prolonged period of heavy
rainfall to result in flash flooding.

Wegman

Day 2
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
GEORGIA AND SOUTH CAROLINA...

20z Update: Main change to the inherited risk areas was to expand=20
the Slight risk to the GA/SC coast. Overall guidance is split on=20
where convergence will be maximized, with the GFS/ECMWF and a=20
couple HREF members inland over GA and SC, the HRRR and Gem Reg=20
more towards the coast, and the ECMWF AIFS in between. Confidence=20
in which model camp is right remains low...thus the Slight risk was
expanded to include both possible outcomes. Overall still think=20
this event has some higher end potential along a narrow axis. The=20
dry antecedent conditions will initially limit the flood=20
risk...however the ingredients are there to overcome this wherever=20 convergence can be maximized for the longest time. Could eventually
need a targeted MDT risk, but given continued uncertainty with the
axis of max rainfall, think a Slight should suffice for now.

Chenard

...Previous Discussion...

A large plume of deep tropical moisture will overspread all of
Florida and move into Georgia and South Carolina on Wednesday and
Wednesday night. This same plume is home to T.S. Rafael down in the
Caribbean. PWATs will increase to as high as 2.25 inches, meaning
the storms expected to form will have plenty of moisture to convert
to heavy rainfall. The front over the Ohio Valley is unlikely to
play too much of a role in the storms over Georgia and South
Carolina. Rather, the guidance suggests a secondary front will from
at the leading edge of the moisture plume that will likely be
enhanced by the right entrance region of the upper level jet
streak, as well as possibly some upslope component (especially in
South Carolina). Regardless of the primary lifting mechanism, there
is good agreement in the guidance for an area of 3 to 5 inches of
rain (though likely much higher amounts will be embedded) in the
Slight Risk area, which is a small increase in amounts from the
previous forecast.

As with areas further west the past several days, this area has
also been incredibly dry lately, with many areas not having seen
appreciable rain in a month. For the swampy and sandy areas, this
will mean it will take a lot of rain before runoff converts to
flooding. Further north across interior SC and GA, the clay soils
are likely quite hydrophobic due to the recent dry weather, which
will notably increase runoff once the heavy rain gets started.
Thus, locally increased impacts are possible. An internal higher-
end Slight area was introduced for the peak rainfall area of east-
central Georgia and west central South Carolina for this potential.

Since this plume is home to T.S. Rafael, this would be considered a
predecessor rain event (PRE) if Rafael were to head towards the Big
Bend and GA/SC. However, since the latest forecasts keep Rafael
tracking westward in the Gulf this rainfall event is not considered
a PRE.

Wegman

Day 3
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST AS WELL AS FOR PORTIONS OF THE SOUTHERN PLAINS...

20z Update: Only minimal changes to the inherited Marginal risk=20
areas. Outer banding east of Rafael could be scraping the Gulf=20
Coast of FL, although lingering uncertainty with exactly how close
the system will track to the coast. Likely to have ongoing=20
convection over portions of GA/SC and depending on what happens on
day 2 could eventually need a Slight risk for the morning=20
hours. However the peak of the heaviest rainfall should be=20
Wednesday afternoon and night, with activity on a downward trend=20
Thursday. So for now will stick with the Marginal and continue to=20
monitor.

Over the southern Plains models are trending a bit slower and south
with the mid/upper low. The GFS (which had been an outlier) had=20
the biggest jump, with the 12z run now more in line with the rest=20
of the models. However there still may be room for a slower and=20
further south solution...with both the UKMET and ECMWF AIFS showing
something slower/south. Do think the ingredients in place will=20
eventually support a Slight risk, but given the lingering=20
uncertainty with placement opted to hold things at Marginal for=20
now.

Chenard

...Previous Discussion...

...Southeast...

The cold front over the Appalachians that will drive the Day
2/Wednesday rainfall event will move southward to coastal South
Carolina and southern Georgia Thursday and Thursday night. The
southerly flow of deep tropical moisture ahead of the front will
abate somewhat in favor of a more neutral easterly flow. This will
keep periods of heavy rain going...but both less widespread, less
persistent, and less heavily. The core of heaviest rain will shift
to the coast of SC/GA and north FL, but since most of this area is
likely to not have seen substantive amounts of rain on Wednesday,
and the coastal swamps can usually handle a lot of rainfall with
few problems, have opted to keep the area in a Marginal Risk for
this update. However, recent model trends have been for the
heaviest rain to increase with time as the CAMs move into this
period of time. Should that happen a Slight Risk will likely be
necessary.

...Southern Plains...

A potent upper level low will begin to eject out of the Southwest
and into the southern Plains on Thursday. A strong cold front will
develop as a result with plentiful snow into much of northeastern
New Mexico. This area was trimmed from the Marginal Risk with this
update. For the rest of the Marginal Risk area, some Gulf moisture
will be captured and advected northward across north Texas and
Oklahoma, but amounts will be somewhat limited. With only broad
forcing from an upper level jet streak but few coherent features
away from the strong cold front, the rainfall footprint will be
broad and disorganized. This area has seen plentiful rainfall over
the past few days, so the additional rainfall, while not much, may
still cause isolated instances of flash flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-GPFX5mZi78XCAsackrNaNP_KASJRWb5ET5PH0o6BTAO= AgeWTbX2njSxeXtCi3XXHZorabv7HIk_PjZYFjhpOaROrLM$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-GPFX5mZi78XCAsackrNaNP_KASJRWb5ET5PH0o6BTAO= AgeWTbX2njSxeXtCi3XXHZorabv7HIk_PjZYFjhpGNEH8kM$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-GPFX5mZi78XCAsackrNaNP_KASJRWb5ET5PH0o6BTAO= AgeWTbX2njSxeXtCi3XXHZorabv7HIk_PjZYFjhpQXbgROc$=20

=3D =3D =3D
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FOUS30 KWBC 060051
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
751 PM EST Tue Nov 5 2024

Day 1
Valid 01Z Wed Nov 06 2024 - 12Z Wed Nov 06 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER TO MID MISSISSIPPI AND LOWER OHIO VALLEYS...

...01z Update...

Little change needed to the inherited Slight Risk for overnight, as
the expectation for localized 2-3" totals remains on track. The
edges of the Slight and Marginal Risk areas were adjusted a bit,
based on observational and model trends.=20

Churchill


...1600Z Update...

Overall, modest changes made for the late-morning update to
account for the latest 12Z HREF guidance and recent HRRR trends.
There has been some overall tightening of the QPF gradient from the
lower MS Valley up into the lower OH Valley for the late-day and
overnight hours, but still a threat for a ribbon of locally heavy
rainfall totals. This will include areas from northwest MS through
western TN and western KY where the latest guidance still supports
a 40 to 45 kt southerly low-level jet ahead of the cold front
approaching the area, and thus a channel of rather strong moisture
transport. Instability though is overall expected to rather modest
and this will likely tend to cut down on the rainfall rates of the
areal shower and thunderstorm activity. Nevertheless, there may be
some localized training of the convection this evening, especially
in the 00Z to 06Z time period, and a few pockets of 2 to 3 inch
rainfall totals will be possible.

Based on this, the Slight Risk area has been maintained although
adjusted just slightly off to the east and trimmed in areal extent
to account for the 12Z HREF consensus. Given the eastward advance
of the overall rainfall shield currently over the lower/middle MS
Valley and southeast TX, the western portion of the Marginal Risk
area has been trimmed away.

Orrison


...Previous Discussion...

A cold front tracking east across the middle of the country is
expected to stall out generally along the Mississippi and Ohio
Rivers late tonight. Southerly flow off the Gulf will continue
pumping plentiful moisture into the front. Meanwhile, in the upper
levels, a large longwave trough over the west will establish itself
as a positively tilted trough by tonight as it digs southwestward
over the Southwest. Before it does so, the last potent shortwave of
the "old" trough will race northeastward into the Great Lakes as
the leading edge of the trough becomes a roughly straight line
southwesterly from the Southwest right through into eastern Canada.

The potent shortwave and associated surface low will both race
northeastward through the period. While they're over the upper
Mississippi Valley, they will move the front currently stalled from
Texas through Michigan eastward a bit to align with the Slight and
Marginal Risk areas along the Mississippi and Ohio Rivers. This
will give the hard hit northwestern Arkansas region a break as the
heaviest rain shifts east. However, by tonight, both features will
be well into the Great Lakes and Canada, so the forcing pushing
them east will quickly diminish, resulting in another stall-out of
the front. With continuous Gulf moisture, another round of training thunderstorms is expected up the Mississippi and lower Ohio Rivers
tonight. Given both the prior history of this front stalling as
well as urban concerns in the Memphis area especially, a Slight
Risk area was introduced with this update.

Despite the stalled out front keeping the rainfall largely confined
to a narrow corridor, the upper level forcing quickly weakening
tonight should hold rates and coverage in check much better tonight
as compared to the ongoing storms over Texas, Arkansas and Missouri
right now. Thus, forecast rainfall amounts are considerably lower
today and tonight than yesterday. The Slight is considered a
"lower-end Slight" with any flash flooding impacts expected to be
largely confined to low-lying flood prone areas and urban areas.
Like areas further west, this area has also been very dry prior to
this rainfall, so it will still take a prolonged period of heavy
rainfall to result in flash flooding.

Wegman

Day 2
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
GEORGIA AND SOUTH CAROLINA...

20z Update: Main change to the inherited risk areas was to expand
the Slight risk to the GA/SC coast. Overall guidance is split on
where convergence will be maximized, with the GFS/ECMWF and a
couple HREF members inland over GA and SC, the HRRR and Gem Reg
more towards the coast, and the ECMWF AIFS in between. Confidence
in which model camp is right remains low...thus the Slight risk was
expanded to include both possible outcomes. Overall still think
this event has some higher end potential along a narrow axis. The
dry antecedent conditions will initially limit the flood
risk...however the ingredients are there to overcome this wherever
convergence can be maximized for the longest time. Could eventually
need a targeted MDT risk, but given continued uncertainty with the
axis of max rainfall, think a Slight should suffice for now.

Chenard

...Previous Discussion...

A large plume of deep tropical moisture will overspread all of
Florida and move into Georgia and South Carolina on Wednesday and
Wednesday night. This same plume is home to T.S. Rafael down in the
Caribbean. PWATs will increase to as high as 2.25 inches, meaning
the storms expected to form will have plenty of moisture to convert
to heavy rainfall. The front over the Ohio Valley is unlikely to
play too much of a role in the storms over Georgia and South
Carolina. Rather, the guidance suggests a secondary front will from
at the leading edge of the moisture plume that will likely be
enhanced by the right entrance region of the upper level jet
streak, as well as possibly some upslope component (especially in
South Carolina). Regardless of the primary lifting mechanism, there
is good agreement in the guidance for an area of 3 to 5 inches of
rain (though likely much higher amounts will be embedded) in the
Slight Risk area, which is a small increase in amounts from the
previous forecast.

As with areas further west the past several days, this area has
also been incredibly dry lately, with many areas not having seen
appreciable rain in a month. For the swampy and sandy areas, this
will mean it will take a lot of rain before runoff converts to
flooding. Further north across interior SC and GA, the clay soils
are likely quite hydrophobic due to the recent dry weather, which
will notably increase runoff once the heavy rain gets started.
Thus, locally increased impacts are possible. An internal higher-
end Slight area was introduced for the peak rainfall area of east-
central Georgia and west central South Carolina for this potential.

Since this plume is home to T.S. Rafael, this would be considered a
predecessor rain event (PRE) if Rafael were to head towards the Big
Bend and GA/SC. However, since the latest forecasts keep Rafael
tracking westward in the Gulf this rainfall event is not considered
a PRE.

Wegman

Day 3
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST AS WELL AS FOR PORTIONS OF THE SOUTHERN PLAINS...

20z Update: Only minimal changes to the inherited Marginal risk
areas. Outer banding east of Rafael could be scraping the Gulf
Coast of FL, although lingering uncertainty with exactly how close
the system will track to the coast. Likely to have ongoing
convection over portions of GA/SC and depending on what happens on
day 2 could eventually need a Slight risk for the morning
hours. However the peak of the heaviest rainfall should be
Wednesday afternoon and night, with activity on a downward trend
Thursday. So for now will stick with the Marginal and continue to
monitor.

Over the southern Plains models are trending a bit slower and south
with the mid/upper low. The GFS (which had been an outlier) had
the biggest jump, with the 12z run now more in line with the rest
of the models. However there still may be room for a slower and
further south solution...with both the UKMET and ECMWF AIFS showing
something slower/south. Do think the ingredients in place will
eventually support a Slight risk, but given the lingering
uncertainty with placement opted to hold things at Marginal for
now.

Chenard

...Previous Discussion...

...Southeast...

The cold front over the Appalachians that will drive the Day
2/Wednesday rainfall event will move southward to coastal South
Carolina and southern Georgia Thursday and Thursday night. The
southerly flow of deep tropical moisture ahead of the front will
abate somewhat in favor of a more neutral easterly flow. This will
keep periods of heavy rain going...but both less widespread, less
persistent, and less heavily. The core of heaviest rain will shift
to the coast of SC/GA and north FL, but since most of this area is
likely to not have seen substantive amounts of rain on Wednesday,
and the coastal swamps can usually handle a lot of rainfall with
few problems, have opted to keep the area in a Marginal Risk for
this update. However, recent model trends have been for the
heaviest rain to increase with time as the CAMs move into this
period of time. Should that happen a Slight Risk will likely be
necessary.

...Southern Plains...

A potent upper level low will begin to eject out of the Southwest
and into the southern Plains on Thursday. A strong cold front will
develop as a result with plentiful snow into much of northeastern
New Mexico. This area was trimmed from the Marginal Risk with this
update. For the rest of the Marginal Risk area, some Gulf moisture
will be captured and advected northward across north Texas and
Oklahoma, but amounts will be somewhat limited. With only broad
forcing from an upper level jet streak but few coherent features
away from the strong cold front, the rainfall footprint will be
broad and disorganized. This area has seen plentiful rainfall over
the past few days, so the additional rainfall, while not much, may
still cause isolated instances of flash flooding.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5aLzdgNXd9cMNSJoMESFKHyE-uGIdMeKnOYleKgGNy1s= ZxjYiMegJTrWfOdrrvD0Tlr3hLFYs_zIoEcpHsdu6uXCo74$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5aLzdgNXd9cMNSJoMESFKHyE-uGIdMeKnOYleKgGNy1s= ZxjYiMegJTrWfOdrrvD0Tlr3hLFYs_zIoEcpHsduDl2dF0E$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5aLzdgNXd9cMNSJoMESFKHyE-uGIdMeKnOYleKgGNy1s= ZxjYiMegJTrWfOdrrvD0Tlr3hLFYs_zIoEcpHsdu2-NsLew$=20

=3D =3D =3D
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FOUS30 KWBC 060823
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
323 AM EST Wed Nov 6 2024

Day 1
Valid 12Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF=20
THE SOUTHEAST...

In coordination with CAE/Columbia, SC and FFC/Peachtree City, GA
forecast offices, a Moderate Risk upgrade was introduced with this
update.

A plume of deep tropical moisture, indirectly associated with
Hurricane Rafael will continue overspreading portions of the
Southeast today. The moisture plume will run into a developing
front over Georgia and South Carolina. An upper level jet streak
will add lift to the atmosphere. Late today into this evening, the
nocturnal low level jet's strengthening will kick the moisture=20
advection into high gear. Frontogenesis occurring over Georgia and
South Carolina will act to focus the heavy rain over the narrow
Moderate Risk corridor. Expect training convection to develop
during the evening which will persist through the overnight and
while slowly weakening in the pre-dawn hours, is likely to continue
into western South Carolina into Day 2/Thursday.=20

HREF probabilities show a 20 to 25 percent chance of a 100 year
rainfall event in the Moderate Risk area. FFGs are very high in the
area due to recent dry conditions with only very light rain. This
has likely made some of the clay soils quite hydrophobic. The
hydrophobic soils will likely increase the runoff from the heavy
rain, which will likely quickly exceed FFGs as the heavy rain
likely persists for multiple hours.=20

Wegman

Day 2
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS FOR MUCH OF THE TEXAS PANHANDLE AND WESTERN
OKLAHOMA...

...Southeast...

Heavy rain will be ongoing across Georgia and especially South
Carolina at the start of the period Thursday morning. While the
rainfall will be diminishing in intensity, it's expected after the
much heavier rains of Wednesday night, that the lighter totals
forecast for Thursday will still be influential since antecedent
conditions will be radically different by then as compared to where
they are now. The Slight Risk threat largely is for the Thursday
morning period with lingering rainfall from Wednesday night. Expect
the rain to continue diminishing through the day as the moisture=20
plume shifts westward with Hurricane Rafael.=20

...Texas Panhandle and Western Oklahoma...

A positively tilted longwave trough and associated upper level=20
energy in the form of jet streaks and shortwave energy will support
the development of a strong low over the southern Plains. To the
west, a significant amount of the low's moisture will fall in the=20
form of snow. Where the precipitation will remain as rain, expect
steady heavy rain across the Texas Panhandle and western Oklahoma.
While rates are not generally expected to be notably heavy, the
flood threat will be primarily focused on the long duration of
steady rain, as well as the fact that much of this area was hit
very hard with heavy rain a few days ago, so soils and rivers
remain elevated in this region. Thus, low FFGs support the Slight
Risk upgrade.=20

Wegman

Day 3
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL AND SOUTHERN PLAINS...

The upper level low over the Southwest will eject into the Plains
on Friday. There will be significant upper level energy associated
with the low, which combined with strong frontogenesis, plentiful
Gulf moisture advecting up the Plains on the low level jet, and a
strengthening surface low...expect heavier rainfall amounts across
Oklahoma and Kansas on Friday as compared with Wednesday. While
north Kansas didn't see as much rain a few days back compared with
areas further south...much of the rest of the Slight risk area does
overlap with both the heavy rain from a few days ago but continued
rainfall from Day 2/Thursday. Thus, added an internal higher-end
Slight for western Oklahoma into south Kansas. Depending on how
much rain the area gets on Day 2, there is some potential for a
Moderate Risk upgrade in this area with future updates.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!74Y8Ry1F0J7LgYfzofgh_bd-sNiaU-mrb4vmFnvw9MmF= IIFD8iCbaXVwJpKv1GsbBhMYNh-i4WBhkKWfbzznUoxWxqg$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!74Y8Ry1F0J7LgYfzofgh_bd-sNiaU-mrb4vmFnvw9MmF= IIFD8iCbaXVwJpKv1GsbBhMYNh-i4WBhkKWfbzznlxc48aA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!74Y8Ry1F0J7LgYfzofgh_bd-sNiaU-mrb4vmFnvw9MmF= IIFD8iCbaXVwJpKv1GsbBhMYNh-i4WBhkKWfbzznAI-BxJM$=20

=3D =3D =3D
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FOUS30 KWBC 061555
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1055 AM EST Wed Nov 6 2024

Day 1
Valid 16Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

1600Z Update...

A Marginal Risk area has been added to portions of central to
northeast LA and also a small part of southwest MS to account for
the ongoing slow-moving areas of heavy showers and thunderstorms
across the region that are focusing along and out ahead of a
quasi-stationary front. Please consult MPD #1131 for more details
on this. Convective trends across this region will continue to be
closely monitored through the afternoon hours for additional
convective development.

Elsewhere, the 12Z HREF guidance and recent HRRR guidance continues
to support the development and expansion of broken areas of heavy
showers and thunderstorms across the interior of the Southeast
beginning later this afternoon and heading into the overnight
hours. However, there has been a trend to concentrate the heaviest
convective rainfall threat a bit farther south and east and a bit
deeper into the coastal plain of southern and eastern GA and the SC
Lowcountry. Additionally, there are multiple HREF models that are
quite heavy with the rainfall potential across parts of the FL
Panhandle. Regionally, the potential exists for as much as 4 to 8
inches of rain, with some isolated 10+ inch totals being supported
by 12Z/Thursday. The 12Z HREF guidance shows 50 to 80 percent
probabilities of seeing 5+ inches of rain from eastern parts of the
FL Panhandle northeastward into the SC Lowcountry, and in a focused
manner across parts of east-central GA and along the SC border,
there are 60 to 80 percent probabilities of seeing 8+ inch=20
rainfall totals. The heavy rains are again expected to be the=20
result of increasing moisture transport poleward of Hurricane=20
Rafael and interaction with an inverted surface trough, and with=20 right-entrance region upper-level jet dynamics providing deeper=20
layer ascent. Given the setup, which will favor rainfall rates of 2
to 3+ inches/hour and these impressive totals, there will be a=20
strong concern for areas of high-impact flash flooding. These
latest trends have necessitated the need to adjust the Slight and
Moderate Risk areas farther south and east.

Related to Hurricane Rafael, there may be some potential for outer bands
of convection to impact portions of the lower FL Keys going through
tonight, and as a result the Marginal Risk area has been maintained
for this area.

Orrison


Previous discussion...

In coordination with CAE/Columbia, SC and FFC/Peachtree City, GA
forecast offices, a Moderate Risk upgrade was introduced with this
update.

A plume of deep tropical moisture, indirectly associated with
Hurricane Rafael will continue overspreading portions of the
Southeast today. The moisture plume will run into a developing
front over Georgia and South Carolina. An upper level jet streak
will add lift to the atmosphere. Late today into this evening, the
nocturnal low level jet's strengthening will kick the moisture
advection into high gear. Frontogenesis occurring over Georgia and
South Carolina will act to focus the heavy rain over the narrow
Moderate Risk corridor. Expect training convection to develop
during the evening which will persist through the overnight and
while slowly weakening in the pre-dawn hours, is likely to continue
into western South Carolina into Day 2/Thursday.

HREF probabilities show a 20 to 25 percent chance of a 100 year
rainfall event in the Moderate Risk area. FFGs are very high in the
area due to recent dry conditions with only very light rain. This
has likely made some of the clay soils quite hydrophobic. The
hydrophobic soils will likely increase the runoff from the heavy
rain, which will likely quickly exceed FFGs as the heavy rain
likely persists for multiple hours.

Wegman

Day 2
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS FOR MUCH OF THE TEXAS PANHANDLE AND WESTERN
OKLAHOMA...

...Southeast...

Heavy rain will be ongoing across Georgia and especially South
Carolina at the start of the period Thursday morning. While the
rainfall will be diminishing in intensity, it's expected after the
much heavier rains of Wednesday night, that the lighter totals
forecast for Thursday will still be influential since antecedent
conditions will be radically different by then as compared to where
they are now. The Slight Risk threat largely is for the Thursday
morning period with lingering rainfall from Wednesday night. Expect
the rain to continue diminishing through the day as the moisture
plume shifts westward with Hurricane Rafael.

...Texas Panhandle and Western Oklahoma...

A positively tilted longwave trough and associated upper level
energy in the form of jet streaks and shortwave energy will support
the development of a strong low over the southern Plains. To the
west, a significant amount of the low's moisture will fall in the
form of snow. Where the precipitation will remain as rain, expect
steady heavy rain across the Texas Panhandle and western Oklahoma.
While rates are not generally expected to be notably heavy, the
flood threat will be primarily focused on the long duration of
steady rain, as well as the fact that much of this area was hit
very hard with heavy rain a few days ago, so soils and rivers
remain elevated in this region. Thus, low FFGs support the Slight
Risk upgrade.

Wegman

Day 3
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL AND SOUTHERN PLAINS...

The upper level low over the Southwest will eject into the Plains
on Friday. There will be significant upper level energy associated
with the low, which combined with strong frontogenesis, plentiful
Gulf moisture advecting up the Plains on the low level jet, and a
strengthening surface low...expect heavier rainfall amounts across
Oklahoma and Kansas on Friday as compared with Wednesday. While
north Kansas didn't see as much rain a few days back compared with
areas further south...much of the rest of the Slight risk area does
overlap with both the heavy rain from a few days ago but continued
rainfall from Day 2/Thursday. Thus, added an internal higher-end
Slight for western Oklahoma into south Kansas. Depending on how
much rain the area gets on Day 2, there is some potential for a
Moderate Risk upgrade in this area with future updates.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6tDD55fVIswBGtZkw9-8Fjn7guLUCGaHXUkydY3S-4td= C0qUXNzCf7dEtGZHhh2zby_YACaelSH69TwOrgZKTkN4fWM$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6tDD55fVIswBGtZkw9-8Fjn7guLUCGaHXUkydY3S-4td= C0qUXNzCf7dEtGZHhh2zby_YACaelSH69TwOrgZKd_3UNw8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6tDD55fVIswBGtZkw9-8Fjn7guLUCGaHXUkydY3S-4td= C0qUXNzCf7dEtGZHhh2zby_YACaelSH69TwOrgZKs5PMquc$=20

=3D =3D =3D
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FOUS30 KWBC 062000
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
300 PM EST Wed Nov 6 2024

Day 1
Valid 16Z Wed Nov 06 2024 - 12Z Thu Nov 07 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

1600Z Update...

A Marginal Risk area has been added to portions of central to
northeast LA and also a small part of southwest MS to account for
the ongoing slow-moving areas of heavy showers and thunderstorms
across the region that are focusing along and out ahead of a
quasi-stationary front. Please consult MPD #1131 for more details
on this. Convective trends across this region will continue to be
closely monitored through the afternoon hours for additional
convective development.

Elsewhere, the 12Z HREF guidance and recent HRRR guidance continues
to support the development and expansion of broken areas of heavy
showers and thunderstorms across the interior of the Southeast
beginning later this afternoon and heading into the overnight
hours. However, there has been a trend to concentrate the heaviest
convective rainfall threat a bit farther south and east and a bit
deeper into the coastal plain of southern and eastern GA and the SC
Lowcountry. Additionally, there are multiple HREF models that are
quite heavy with the rainfall potential across parts of the FL
Panhandle. Regionally, the potential exists for as much as 4 to 8
inches of rain, with some isolated 10+ inch totals being supported
by 12Z/Thursday. The 12Z HREF guidance shows 50 to 80 percent
probabilities of seeing 5+ inches of rain from eastern parts of the
FL Panhandle northeastward into the SC Lowcountry, and in a focused
manner across parts of east-central GA and along the SC border,
there are 60 to 80 percent probabilities of seeing 8+ inch
rainfall totals. The heavy rains are again expected to be the
result of increasing moisture transport poleward of Hurricane
Rafael and interaction with an inverted surface trough, and with
right-entrance region upper-level jet dynamics providing deeper
layer ascent. Given the setup, which will favor rainfall rates of 2
to 3+ inches/hour and these impressive totals, there will be a
strong concern for areas of high-impact flash flooding. These
latest trends have necessitated the need to adjust the Slight and
Moderate Risk areas farther south and east.

Related to Hurricane Rafael, there may be some potential for outer bands
of convection to impact portions of the lower FL Keys going through
tonight, and as a result the Marginal Risk area has been maintained
for this area.

Orrison


Previous discussion...

In coordination with CAE/Columbia, SC and FFC/Peachtree City, GA
forecast offices, a Moderate Risk upgrade was introduced with this
update.

A plume of deep tropical moisture, indirectly associated with
Hurricane Rafael will continue overspreading portions of the
Southeast today. The moisture plume will run into a developing
front over Georgia and South Carolina. An upper level jet streak
will add lift to the atmosphere. Late today into this evening, the
nocturnal low level jet's strengthening will kick the moisture
advection into high gear. Frontogenesis occurring over Georgia and
South Carolina will act to focus the heavy rain over the narrow
Moderate Risk corridor. Expect training convection to develop
during the evening which will persist through the overnight and
while slowly weakening in the pre-dawn hours, is likely to continue
into western South Carolina into Day 2/Thursday.

HREF probabilities show a 20 to 25 percent chance of a 100 year
rainfall event in the Moderate Risk area. FFGs are very high in the
area due to recent dry conditions with only very light rain. This
has likely made some of the clay soils quite hydrophobic. The
hydrophobic soils will likely increase the runoff from the heavy
rain, which will likely quickly exceed FFGs as the heavy rain
likely persists for multiple hours.

Wegman

Day 2
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS PORTIONS OF TEXAS PANHANDLE AND WESTERN=20
OKLAHOMA...

20z Update: Slight risk reasoning still holds over GA and SC. Only
adjustment was to expand the risk towards the coast following=20
model trends.

Convection Thursday evening into the overnight hours should drive=20
at least some flash flood risk over portions of TX and OK. Plenty=20
of large scale forcing and moisture in place to drive a widespread=20 convective risk...with the main uncertainty more relating to the=20
degree of instability present. The inherited Slight risk was=20
shifted southward with this update into more of TX. This is=20
supported by the 12z HREF probabilities and the 12z GEFS based=20
machine learning ERO guidance. The area encompassed by the Slight=20
risk should see slightly better instability which will allow for=20
the potential of higher rainfall rates.

Chenard

...Previous Discussion...

...Southeast...

Heavy rain will be ongoing across Georgia and especially South
Carolina at the start of the period Thursday morning. While the
rainfall will be diminishing in intensity, it's expected after the
much heavier rains of Wednesday night, that the lighter totals
forecast for Thursday will still be influential since antecedent
conditions will be radically different by then as compared to where
they are now. The Slight Risk threat largely is for the Thursday
morning period with lingering rainfall from Wednesday night. Expect
the rain to continue diminishing through the day as the moisture
plume shifts westward with Hurricane Rafael.

...Texas Panhandle and Western Oklahoma...

A positively tilted longwave trough and associated upper level
energy in the form of jet streaks and shortwave energy will support
the development of a strong low over the southern Plains. To the
west, a significant amount of the low's moisture will fall in the
form of snow. Where the precipitation will remain as rain, expect
steady heavy rain across the Texas Panhandle and western Oklahoma.
While rates are not generally expected to be notably heavy, the
flood threat will be primarily focused on the long duration of
steady rain, as well as the fact that much of this area was hit
very hard with heavy rain a few days ago, so soils and rivers
remain elevated in this region. Thus, low FFGs support the Slight
Risk upgrade.

Wegman

Day 3
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL AND SOUTHERN PLAINS...

20z Update: The Slight risk over the Plains was adjusted a bit
southward with this update. This aligns well with the forecast
overlap of instability and moisture convergence. We continue to
carry higher end Slight risk probabilities across portions of TX
into western OK. Given the above average soil saturation already=20
in place, and the forecast overlap of rainfall Thursday and Friday=20
over this area, some instances of flash flooding are becoming=20
increasingly likely. Still some uncertainty with exactly where the=20
best overlap of convection and thus highest 2 day rainfall totals=20
will be...with the favored axis currently from north central TX=20
into southwest OK, where 3-5" is forecast. If confidence in this=20
area increases and/or totals trend up over 5" then a MDT risk=20
upgrade may eventually be needed.

Chenard

...Previous Discussion...

The upper level low over the Southwest will eject into the Plains
on Friday. There will be significant upper level energy associated
with the low, which combined with strong frontogenesis, plentiful
Gulf moisture advecting up the Plains on the low level jet, and a
strengthening surface low...expect heavier rainfall amounts across
Oklahoma and Kansas on Friday as compared with Wednesday. While
north Kansas didn't see as much rain a few days back compared with
areas further south...much of the rest of the Slight risk area does
overlap with both the heavy rain from a few days ago but continued
rainfall from Day 2/Thursday. Thus, added an internal higher-end
Slight for western Oklahoma into south Kansas. Depending on how
much rain the area gets on Day 2, there is some potential for a
Moderate Risk upgrade in this area with future updates.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-kcT4Kv2phf6IWgBnDtkWv3_-b850FTZ9A_mmVI7hbPV= J6L_vi4Dvy3_IZTS93tHIFjNSm9Xk2rCHJ6PX-Rcp2EqBNA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-kcT4Kv2phf6IWgBnDtkWv3_-b850FTZ9A_mmVI7hbPV= J6L_vi4Dvy3_IZTS93tHIFjNSm9Xk2rCHJ6PX-Rc-ZphcGE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-kcT4Kv2phf6IWgBnDtkWv3_-b850FTZ9A_mmVI7hbPV= J6L_vi4Dvy3_IZTS93tHIFjNSm9Xk2rCHJ6PX-Rcjiz1sso$=20

=3D =3D =3D
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FOUS30 KWBC 070059
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
759 PM EST Wed Nov 6 2024

Day 1
Valid 01Z Thu Nov 07 2024 - 12Z Thu Nov 07 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

0100Z Update...

Not many changes to the outlook areas across the Southeast. A
Moderate Risk was maintained from southern Georgia to central South
Carolina, where heavy rainfall is likely to continue overnight.
Latest HREF guidance shows high neighborhood probabilities (greater
than 50 percent) for additional amounts of 3 inches or more=20
throughout the Moderate Risk area. High probabilities for=20
additional amounts of 5 inches or more center near the Georgia-
South Carolina border, partially overlapping an area where MRMS=20
estimates indicate 3-7 inches have already fallen over the past=20
several hours. Refer to WPC MPD #1133 for additional information=20
regarding the anticipated near-term heavy rainfall/flash flooding=20
threat across this region.

Pereira

1600Z Update...

A Marginal Risk area has been added to portions of central to
northeast LA and also a small part of southwest MS to account for
the ongoing slow-moving areas of heavy showers and thunderstorms
across the region that are focusing along and out ahead of a
quasi-stationary front. Please consult MPD #1131 for more details
on this. Convective trends across this region will continue to be
closely monitored through the afternoon hours for additional
convective development.

Elsewhere, the 12Z HREF guidance and recent HRRR guidance continues
to support the development and expansion of broken areas of heavy
showers and thunderstorms across the interior of the Southeast
beginning later this afternoon and heading into the overnight
hours. However, there has been a trend to concentrate the heaviest
convective rainfall threat a bit farther south and east and a bit
deeper into the coastal plain of southern and eastern GA and the SC
Lowcountry. Additionally, there are multiple HREF models that are
quite heavy with the rainfall potential across parts of the FL
Panhandle. Regionally, the potential exists for as much as 4 to 8
inches of rain, with some isolated 10+ inch totals being supported
by 12Z/Thursday. The 12Z HREF guidance shows 50 to 80 percent
probabilities of seeing 5+ inches of rain from eastern parts of the
FL Panhandle northeastward into the SC Lowcountry, and in a focused
manner across parts of east-central GA and along the SC border,
there are 60 to 80 percent probabilities of seeing 8+ inch
rainfall totals. The heavy rains are again expected to be the
result of increasing moisture transport poleward of Hurricane
Rafael and interaction with an inverted surface trough, and with
right-entrance region upper-level jet dynamics providing deeper
layer ascent. Given the setup, which will favor rainfall rates of 2
to 3+ inches/hour and these impressive totals, there will be a
strong concern for areas of high-impact flash flooding. These
latest trends have necessitated the need to adjust the Slight and
Moderate Risk areas farther south and east.

Related to Hurricane Rafael, there may be some potential for outer bands
of convection to impact portions of the lower FL Keys going through
tonight, and as a result the Marginal Risk area has been maintained
for this area.

Orrison


Previous discussion...

In coordination with CAE/Columbia, SC and FFC/Peachtree City, GA
forecast offices, a Moderate Risk upgrade was introduced with this
update.

A plume of deep tropical moisture, indirectly associated with
Hurricane Rafael will continue overspreading portions of the
Southeast today. The moisture plume will run into a developing
front over Georgia and South Carolina. An upper level jet streak
will add lift to the atmosphere. Late today into this evening, the
nocturnal low level jet's strengthening will kick the moisture
advection into high gear. Frontogenesis occurring over Georgia and
South Carolina will act to focus the heavy rain over the narrow
Moderate Risk corridor. Expect training convection to develop
during the evening which will persist through the overnight and
while slowly weakening in the pre-dawn hours, is likely to continue
into western South Carolina into Day 2/Thursday.

HREF probabilities show a 20 to 25 percent chance of a 100 year
rainfall event in the Moderate Risk area. FFGs are very high in the
area due to recent dry conditions with only very light rain. This
has likely made some of the clay soils quite hydrophobic. The
hydrophobic soils will likely increase the runoff from the heavy
rain, which will likely quickly exceed FFGs as the heavy rain
likely persists for multiple hours.

Wegman

Day 2
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS PORTIONS OF TEXAS PANHANDLE AND WESTERN
OKLAHOMA...

20z Update: Slight risk reasoning still holds over GA and SC. Only
adjustment was to expand the risk towards the coast following
model trends.

Convection Thursday evening into the overnight hours should drive
at least some flash flood risk over portions of TX and OK. Plenty
of large scale forcing and moisture in place to drive a widespread
convective risk...with the main uncertainty more relating to the
degree of instability present. The inherited Slight risk was
shifted southward with this update into more of TX. This is
supported by the 12z HREF probabilities and the 12z GEFS based
machine learning ERO guidance. The area encompassed by the Slight
risk should see slightly better instability which will allow for
the potential of higher rainfall rates.

Chenard

...Previous Discussion...

...Southeast...

Heavy rain will be ongoing across Georgia and especially South
Carolina at the start of the period Thursday morning. While the
rainfall will be diminishing in intensity, it's expected after the
much heavier rains of Wednesday night, that the lighter totals
forecast for Thursday will still be influential since antecedent
conditions will be radically different by then as compared to where
they are now. The Slight Risk threat largely is for the Thursday
morning period with lingering rainfall from Wednesday night. Expect
the rain to continue diminishing through the day as the moisture
plume shifts westward with Hurricane Rafael.

...Texas Panhandle and Western Oklahoma...

A positively tilted longwave trough and associated upper level
energy in the form of jet streaks and shortwave energy will support
the development of a strong low over the southern Plains. To the
west, a significant amount of the low's moisture will fall in the
form of snow. Where the precipitation will remain as rain, expect
steady heavy rain across the Texas Panhandle and western Oklahoma.
While rates are not generally expected to be notably heavy, the
flood threat will be primarily focused on the long duration of
steady rain, as well as the fact that much of this area was hit
very hard with heavy rain a few days ago, so soils and rivers
remain elevated in this region. Thus, low FFGs support the Slight
Risk upgrade.

Wegman

Day 3
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL AND SOUTHERN PLAINS...

20z Update: The Slight risk over the Plains was adjusted a bit
southward with this update. This aligns well with the forecast
overlap of instability and moisture convergence. We continue to
carry higher end Slight risk probabilities across portions of TX
into western OK. Given the above average soil saturation already
in place, and the forecast overlap of rainfall Thursday and Friday
over this area, some instances of flash flooding are becoming
increasingly likely. Still some uncertainty with exactly where the
best overlap of convection and thus highest 2 day rainfall totals
will be...with the favored axis currently from north central TX
into southwest OK, where 3-5" is forecast. If confidence in this
area increases and/or totals trend up over 5" then a MDT risk
upgrade may eventually be needed.

Chenard

...Previous Discussion...

The upper level low over the Southwest will eject into the Plains
on Friday. There will be significant upper level energy associated
with the low, which combined with strong frontogenesis, plentiful
Gulf moisture advecting up the Plains on the low level jet, and a
strengthening surface low...expect heavier rainfall amounts across
Oklahoma and Kansas on Friday as compared with Wednesday. While
north Kansas didn't see as much rain a few days back compared with
areas further south...much of the rest of the Slight risk area does
overlap with both the heavy rain from a few days ago but continued
rainfall from Day 2/Thursday. Thus, added an internal higher-end
Slight for western Oklahoma into south Kansas. Depending on how
much rain the area gets on Day 2, there is some potential for a
Moderate Risk upgrade in this area with future updates.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4U7kc6tUKTo8o-AVj0vkW6AMUlmkzl7zGtcSRkO4HEzg= P-WTubyBQE8H1Hm8I_OiHCcmLG3jSNpsvnyw-xitn5kKlVI$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4U7kc6tUKTo8o-AVj0vkW6AMUlmkzl7zGtcSRkO4HEzg= P-WTubyBQE8H1Hm8I_OiHCcmLG3jSNpsvnyw-xitbfjqTEI$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4U7kc6tUKTo8o-AVj0vkW6AMUlmkzl7zGtcSRkO4HEzg= P-WTubyBQE8H1Hm8I_OiHCcmLG3jSNpsvnyw-xitY7tpzSM$=20

=3D =3D =3D
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FOUS30 KWBC 070820
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
320 AM EST Thu Nov 7 2024

Day 1
Valid 12Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS PORTIONS OF WEST TEXAS AND WESTERN OKLAHOMA...

...Southeast...

Heavy rain continues across Georgia and South Carolina this
morning. A nearly stationary front across the region is acting as a
focus for that rainfall, which due to an influx of tropical
moisture moving into the front from the Atlantic remains stuck. The
moisture running into the front is allowing for convective
development along the front in Florida and Georgia, which then=20
advect northeastward into South Carolina. While convective coverage
has been slowly diminishing, along with the storms with the
heaviest rainfall, it's likely that the rain will continue into the
day today. The inherited Slight and Marginal risks were largely
left unchanged with this update, as the rainfall is generally
behaving as expected. Since there will be a very slow drift of the
heaviest rainfall towards the South Carolina coast, which due to
the swampy terrain is generally much better equipped to handle
heavy rainfall rates, a Slight Risk is sufficient to cover the
flash flooding threat, rather than a continuation of the Moderate.

...West Texas and Western Oklahoma...

A strong upper level low over the Southwest will interact with an
LLJ of Gulf moisture and a developing surface low forming ahead of
the upper level low. A large area of rain will develop from the
Texas and Oklahoma Panhandles south and east over portions of the
Cap Rock of Texas and much of Oklahoma west of Oklahoma City.
Instability will be a significant limiting factor on short-term
rainfall rates and the strength of any convection, but the fact
that all of those synoptic systems just described will be very slow
moving should increase the duration of steady rainfall. Since much
of this region was hit hard with heavy rain a few days ago, FFGs
remain low enough that they should be overcome in widely scattered
instances in the Slight Risk area, and in isolated instances in the
Marginal Risk region.=20

Wegman

Day 2
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

The upper level low over the Southwest and its attendant surface=20
low will both continue moving northeast across the Plains on
Friday. With continued influx of Gulf moisture, the typical comma
shaped precipitation footprint will develop from Texas to Oklahoma.
Out west in Colorado and New Mexico the precipitation will be=20
mostly in the form of snow. Where it remains all rain, the heaviest
rain will be from north Texas across Oklahoma and into south
central Kansas. As today, instability will remain the primary
limiting factor for heavy rain in most areas, as MUCAPE values=20
generally stay under 1,000 J/kg. For the Slight Risk area, there
has been a general eastward/faster shift in the guidance, but that
will at least be somewhat offset by the rainfall expected today
over the Panhandles and western Oklahoma.

The rationale for the Slight is two-fold. While somewhat lesser
amounts of rain are expected overall for southern Oklahoma and
Texas...greater instability there will favor at least some storms
capable of heavy rainfall in that area. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the
surface low takes its time getting its act together. So while
instantaneous rates will likely be lower than further south, it
will be made up for by the longer duration of the rain.

Wegman

Day 3
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
LOWER MISSISSIPPI VALLEY...

The upper level low that was driving the heavy rainfall the
previous two days will move faster towards the northeast as it=20
continues its return to the jet stream over the northern tier of=20
states. The area will still have plenty of moisture from the Gulf
to work with as Rafael (or what's left of it) remains over the
central Gulf but the plume of moisture its embedded in continues to
be drawn north ahead of the surface low's strong cold front. The
front will likely be the dominant forcing for storms in this
region. As on Friday, the southern areas of Louisiana and
Mississippi will have the greater moisture and instability, while
further north FFGs are much lower due to recent heavy rainfall.
Thus, once again the Slight Risk is a two-fold combination of
factors that individually increase the flooding risk. The front
should still be slow enough moving that training storms tracking
north along the front could still cause flooding problems,
especially in Louisiana.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!7Ksx_niN22poR5KirpCS2Ws-mJDjP0szc-pxikkrVOvs= hOiB963vFOEAQpetDb5I8ttvN3HdEU5dQ61G8qTeuugY6n4$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!7Ksx_niN22poR5KirpCS2Ws-mJDjP0szc-pxikkrVOvs= hOiB963vFOEAQpetDb5I8ttvN3HdEU5dQ61G8qTenHhPlPE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!7Ksx_niN22poR5KirpCS2Ws-mJDjP0szc-pxikkrVOvs= hOiB963vFOEAQpetDb5I8ttvN3HdEU5dQ61G8qTejHCGzWE$=20

=3D =3D =3D
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FOUS30 KWBC 071600
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1100 AM EST Thu Nov 7 2024

Day 1
Valid 16Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS PORTIONS OF WEST TEXAS AND WESTERN OKLAHOMA...

16Z Excessive Rainfall Discussion Update...
Maintained the Slight Risk areas with few changes across the
Southeast and across portions of West Texas and western Oklahoma.
The latest versions of the HRRR Conest and the HRRR both depict
enough rainfall over the Southeast US that we maintained the Slight
risk with the expectation that the flooding risk from intense
rainfall is confined closer to the coastal portions of Georgia and
South Carolina but any additional rainfall farther inland would
exacerbate on-going flooding from areas soaked overnight. Farther
west...the Slight risk area was expanded a bit northward and
eastward based on the footprint of heaviest rainfall shown by the
HRRR mainly later in the evening and during the overnight hours...NAM
and NAM Conest. With an uptick in QPF...the area of north Texas=20
into southwest Oklahoma is probably a higher-end Slight Risk.=20

Bann

0830Z Excessive Rainfall Discussion...

...Southeast...

Heavy rain continues across Georgia and South Carolina this
morning. A nearly stationary front across the region is acting as a
focus for that rainfall, which due to an influx of tropical
moisture moving into the front from the Atlantic remains stuck. The
moisture running into the front is allowing for convective
development along the front in Florida and Georgia, which then
advect northeastward into South Carolina. While convective coverage
has been slowly diminishing, along with the storms with the
heaviest rainfall, it's likely that the rain will continue into the
day today. The inherited Slight and Marginal risks were largely
left unchanged with this update, as the rainfall is generally
behaving as expected. Since there will be a very slow drift of the
heaviest rainfall towards the South Carolina coast, which due to
the swampy terrain is generally much better equipped to handle
heavy rainfall rates, a Slight Risk is sufficient to cover the
flash flooding threat, rather than a continuation of the Moderate.

...West Texas and Western Oklahoma...

A strong upper level low over the Southwest will interact with an
LLJ of Gulf moisture and a developing surface low forming ahead of
the upper level low. A large area of rain will develop from the
Texas and Oklahoma Panhandles south and east over portions of the
Cap Rock of Texas and much of Oklahoma west of Oklahoma City.
Instability will be a significant limiting factor on short-term
rainfall rates and the strength of any convection, but the fact
that all of those synoptic systems just described will be very slow
moving should increase the duration of steady rainfall. Since much
of this region was hit hard with heavy rain a few days ago, FFGs
remain low enough that they should be overcome in widely scattered
instances in the Slight Risk area, and in isolated instances in the
Marginal Risk region.

Wegman

Day 2
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

The upper level low over the Southwest and its attendant surface
low will both continue moving northeast across the Plains on
Friday. With continued influx of Gulf moisture, the typical comma
shaped precipitation footprint will develop from Texas to Oklahoma.
Out west in Colorado and New Mexico the precipitation will be
mostly in the form of snow. Where it remains all rain, the heaviest
rain will be from north Texas across Oklahoma and into south
central Kansas. As today, instability will remain the primary
limiting factor for heavy rain in most areas, as MUCAPE values
generally stay under 1,000 J/kg. For the Slight Risk area, there
has been a general eastward/faster shift in the guidance, but that
will at least be somewhat offset by the rainfall expected today
over the Panhandles and western Oklahoma.

The rationale for the Slight is two-fold. While somewhat lesser
amounts of rain are expected overall for southern Oklahoma and
Texas...greater instability there will favor at least some storms
capable of heavy rainfall in that area. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the
surface low takes its time getting its act together. So while
instantaneous rates will likely be lower than further south, it
will be made up for by the longer duration of the rain.

Wegman

Day 3
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
LOWER MISSISSIPPI VALLEY...

The upper level low that was driving the heavy rainfall the
previous two days will move faster towards the northeast as it
continues its return to the jet stream over the northern tier of
states. The area will still have plenty of moisture from the Gulf
to work with as Rafael (or what's left of it) remains over the
central Gulf but the plume of moisture its embedded in continues to
be drawn north ahead of the surface low's strong cold front. The
front will likely be the dominant forcing for storms in this
region. As on Friday, the southern areas of Louisiana and
Mississippi will have the greater moisture and instability, while
further north FFGs are much lower due to recent heavy rainfall.
Thus, once again the Slight Risk is a two-fold combination of
factors that individually increase the flooding risk. The front
should still be slow enough moving that training storms tracking
north along the front could still cause flooding problems,
especially in Louisiana.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8PlyZuvFlYNbVoRVroilPndK6RW2rYTnUPsxwq_Ew-2S= xSDxvTsbn_7Le8qyRj7SKENGA6wCkCLHCFc096ShI52B1hA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8PlyZuvFlYNbVoRVroilPndK6RW2rYTnUPsxwq_Ew-2S= xSDxvTsbn_7Le8qyRj7SKENGA6wCkCLHCFc096ShUmDs2Ds$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8PlyZuvFlYNbVoRVroilPndK6RW2rYTnUPsxwq_Ew-2S= xSDxvTsbn_7Le8qyRj7SKENGA6wCkCLHCFc096ShFxcdFYY$=20

=3D =3D =3D
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FOUS30 KWBC 072004
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
304 PM EST Thu Nov 7 2024

Day 1
Valid 16Z Thu Nov 07 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS PORTIONS OF WEST TEXAS AND WESTERN OKLAHOMA...

16Z Excessive Rainfall Discussion Update...
Maintained the Slight Risk areas with few changes across the
Southeast and across portions of West Texas and western Oklahoma.
The latest versions of the HRRR Conest and the HRRR both depict
enough rainfall over the Southeast US that we maintained the Slight
risk with the expectation that the flooding risk from intense
rainfall is confined closer to the coastal portions of Georgia and
South Carolina but any additional rainfall farther inland would
exacerbate on-going flooding from areas soaked overnight. Farther
west...the Slight risk area was expanded a bit northward and
eastward based on the footprint of heaviest rainfall shown by the
HRRR mainly later in the evening and during the overnight hours...NAM
and NAM Conest. With an uptick in QPF...the area of north Texas
into southwest Oklahoma is probably a higher-end Slight Risk.

Bann

0830Z Excessive Rainfall Discussion...

...Southeast...

Heavy rain continues across Georgia and South Carolina this
morning. A nearly stationary front across the region is acting as a
focus for that rainfall, which due to an influx of tropical
moisture moving into the front from the Atlantic remains stuck. The
moisture running into the front is allowing for convective
development along the front in Florida and Georgia, which then
advect northeastward into South Carolina. While convective coverage
has been slowly diminishing, along with the storms with the
heaviest rainfall, it's likely that the rain will continue into the
day today. The inherited Slight and Marginal risks were largely
left unchanged with this update, as the rainfall is generally
behaving as expected. Since there will be a very slow drift of the
heaviest rainfall towards the South Carolina coast, which due to
the swampy terrain is generally much better equipped to handle
heavy rainfall rates, a Slight Risk is sufficient to cover the
flash flooding threat, rather than a continuation of the Moderate.

...West Texas and Western Oklahoma...

A strong upper level low over the Southwest will interact with an
LLJ of Gulf moisture and a developing surface low forming ahead of
the upper level low. A large area of rain will develop from the
Texas and Oklahoma Panhandles south and east over portions of the
Cap Rock of Texas and much of Oklahoma west of Oklahoma City.
Instability will be a significant limiting factor on short-term
rainfall rates and the strength of any convection, but the fact
that all of those synoptic systems just described will be very slow
moving should increase the duration of steady rainfall. Since much
of this region was hit hard with heavy rain a few days ago, FFGs
remain low enough that they should be overcome in widely scattered
instances in the Slight Risk area, and in isolated instances in the
Marginal Risk region.

Wegman

Day 2
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

20z Update: Minimal changes to the inherited Slight risk area.
Convection is likely to be ongoing at 12z Friday across north
central TX into central OK, and rainfall today/tonight should
result in more saturated conditions by 12z. Thus there is likely=20
to be some flash flood risk that continues into Friday...although
by this time less instability and an increased easterly motion to=20
convection should limit the magnitude of the threat. Thus a Slight=20
risk should suffice. The convection over central TX will have more=20 instability to work with Friday afternoon and evening, but should=20
tend to be more progressive in nature. Although some cell mergers=20
could result in a Slight risk of flash flooding.

Chenard

...Previous Discussion...

The upper level low over the Southwest and its attendant surface
low will both continue moving northeast across the Plains on
Friday. With continued influx of Gulf moisture, the typical comma
shaped precipitation footprint will develop from Texas to Oklahoma.
Out west in Colorado and New Mexico the precipitation will be
mostly in the form of snow. Where it remains all rain, the heaviest
rain will be from north Texas across Oklahoma and into south
central Kansas. As today, instability will remain the primary
limiting factor for heavy rain in most areas, as MUCAPE values
generally stay under 1,000 J/kg. For the Slight Risk area, there
has been a general eastward/faster shift in the guidance, but that
will at least be somewhat offset by the rainfall expected today
over the Panhandles and western Oklahoma.

The rationale for the Slight is two-fold. While somewhat lesser
amounts of rain are expected overall for southern Oklahoma and
Texas...greater instability there will favor at least some storms
capable of heavy rainfall in that area. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the
surface low takes its time getting its act together. So while
instantaneous rates will likely be lower than further south, it
will be made up for by the longer duration of the rain.

Wegman

Day 3
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF=20
THE LOWER MISSISSIPPI VALLEY...

20z Update: Main change was a modest eastward shift to the Slight
risk over MS, and a removal over portions of AR/MO following model
trends. The highest threat of 3"+ rainfall totals still looks to=20
be across portions of LA and MS where moisture streaming north of=20
Rafael will interact with the front and upper jet. Still some=20
uncertainty on exactly how this interaction plays out, but there is
a growing signal for the potential of 3-5" (locally higher) of=20
rain somewhere over the lower MS Valley.

Chenard

...Previous Discussion...

The upper level low that was driving the heavy rainfall the
previous two days will move faster towards the northeast as it
continues its return to the jet stream over the northern tier of
states. The area will still have plenty of moisture from the Gulf
to work with as Rafael (or what's left of it) remains over the
central Gulf but the plume of moisture its embedded in continues to
be drawn north ahead of the surface low's strong cold front. The
front will likely be the dominant forcing for storms in this
region. As on Friday, the southern areas of Louisiana and
Mississippi will have the greater moisture and instability, while
further north FFGs are much lower due to recent heavy rainfall.
Thus, once again the Slight Risk is a two-fold combination of
factors that individually increase the flooding risk. The front
should still be slow enough moving that training storms tracking
north along the front could still cause flooding problems,
especially in Louisiana.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6nehDMRZ75cJy76cyyEZ8c3DMdEWd4ynXxYuv52Iy9HD= yWK4VDvocoYRof8t8n-SaopyEGWsRBeyFAtt0ZmghB_WJaQ$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6nehDMRZ75cJy76cyyEZ8c3DMdEWd4ynXxYuv52Iy9HD= yWK4VDvocoYRof8t8n-SaopyEGWsRBeyFAtt0ZmgTqqPe5Y$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6nehDMRZ75cJy76cyyEZ8c3DMdEWd4ynXxYuv52Iy9HD= yWK4VDvocoYRof8t8n-SaopyEGWsRBeyFAtt0ZmgB288_7g$=20

=3D =3D =3D
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FOUS30 KWBC 080119
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
819 PM EST Thu Nov 7 2024

Day 1
Valid 01Z Fri Nov 08 2024 - 12Z Fri Nov 08 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF WEST
TEXAS AND WESTERN OKLAHOMA...


01Z Update...
Across Texas and Oklahoma, adjusted the Slight Risk area where=20
recent runs of the HRRR and current radar trends supported an=20
eastward shift of the Slight Risk area. Ongoing convection from the
Concho Valley northward into portions of the Texas Panhandle and=20 southwestern Oklahoma is expected to continue to develop with=20
north-south training contributing to locally heavy amounts.=20
Neighborhood probabilities from the 18Z HREF indicate that local=20
amounts of 2-3 inches are likely within the Slight Risk area, with=20
some potential for amounts of 5 inches or more, especially across=20
portions of Northwest Texas.

Across the Southeast, removed the Slight Risk area, but maintained
a Marginal Risk from the eastern Florida Panhandle northeastward=20
to the South Carolina Lowcountry. For much of the area, the airmass
has stabilized -- limiting the potential for widespread additional
heavy rainfall rates. However, some slow-moving storms early in=20
the period, including ongoing storms near the Florida-Georgia
border, may pose an isolated flash flooding threat.

Pereira=20

16Z Excessive Rainfall Discussion Update...
Maintained the Slight Risk areas with few changes across the
Southeast and across portions of West Texas and western Oklahoma.
The latest versions of the HRRR Conest and the HRRR both depict
enough rainfall over the Southeast US that we maintained the Slight
risk with the expectation that the flooding risk from intense
rainfall is confined closer to the coastal portions of Georgia and
South Carolina but any additional rainfall farther inland would
exacerbate on-going flooding from areas soaked overnight. Farther
west...the Slight risk area was expanded a bit northward and
eastward based on the footprint of heaviest rainfall shown by the
HRRR mainly later in the evening and during the overnight hours...NAM
and NAM Conest. With an uptick in QPF...the area of north Texas
into southwest Oklahoma is probably a higher-end Slight Risk.

Bann

0830Z Excessive Rainfall Discussion...

...Southeast...

Heavy rain continues across Georgia and South Carolina this
morning. A nearly stationary front across the region is acting as a
focus for that rainfall, which due to an influx of tropical
moisture moving into the front from the Atlantic remains stuck. The
moisture running into the front is allowing for convective
development along the front in Florida and Georgia, which then
advect northeastward into South Carolina. While convective coverage
has been slowly diminishing, along with the storms with the
heaviest rainfall, it's likely that the rain will continue into the
day today. The inherited Slight and Marginal risks were largely
left unchanged with this update, as the rainfall is generally
behaving as expected. Since there will be a very slow drift of the
heaviest rainfall towards the South Carolina coast, which due to
the swampy terrain is generally much better equipped to handle
heavy rainfall rates, a Slight Risk is sufficient to cover the
flash flooding threat, rather than a continuation of the Moderate.

...West Texas and Western Oklahoma...

A strong upper level low over the Southwest will interact with an
LLJ of Gulf moisture and a developing surface low forming ahead of
the upper level low. A large area of rain will develop from the
Texas and Oklahoma Panhandles south and east over portions of the
Cap Rock of Texas and much of Oklahoma west of Oklahoma City.
Instability will be a significant limiting factor on short-term
rainfall rates and the strength of any convection, but the fact
that all of those synoptic systems just described will be very slow
moving should increase the duration of steady rainfall. Since much
of this region was hit hard with heavy rain a few days ago, FFGs
remain low enough that they should be overcome in widely scattered
instances in the Slight Risk area, and in isolated instances in the
Marginal Risk region.

Wegman

Day 2
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

20z Update: Minimal changes to the inherited Slight risk area.
Convection is likely to be ongoing at 12z Friday across north
central TX into central OK, and rainfall today/tonight should
result in more saturated conditions by 12z. Thus there is likely
to be some flash flood risk that continues into Friday...although
by this time less instability and an increased easterly motion to
convection should limit the magnitude of the threat. Thus a Slight
risk should suffice. The convection over central TX will have more
instability to work with Friday afternoon and evening, but should
tend to be more progressive in nature. Although some cell mergers
could result in a Slight risk of flash flooding.

Chenard

...Previous Discussion...

The upper level low over the Southwest and its attendant surface
low will both continue moving northeast across the Plains on
Friday. With continued influx of Gulf moisture, the typical comma
shaped precipitation footprint will develop from Texas to Oklahoma.
Out west in Colorado and New Mexico the precipitation will be
mostly in the form of snow. Where it remains all rain, the heaviest
rain will be from north Texas across Oklahoma and into south
central Kansas. As today, instability will remain the primary
limiting factor for heavy rain in most areas, as MUCAPE values
generally stay under 1,000 J/kg. For the Slight Risk area, there
has been a general eastward/faster shift in the guidance, but that
will at least be somewhat offset by the rainfall expected today
over the Panhandles and western Oklahoma.

The rationale for the Slight is two-fold. While somewhat lesser
amounts of rain are expected overall for southern Oklahoma and
Texas...greater instability there will favor at least some storms
capable of heavy rainfall in that area. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the
surface low takes its time getting its act together. So while
instantaneous rates will likely be lower than further south, it
will be made up for by the longer duration of the rain.

Wegman

Day 3
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE LOWER MISSISSIPPI VALLEY...

20z Update: Main change was a modest eastward shift to the Slight
risk over MS, and a removal over portions of AR/MO following model
trends. The highest threat of 3"+ rainfall totals still looks to
be across portions of LA and MS where moisture streaming north of
Rafael will interact with the front and upper jet. Still some
uncertainty on exactly how this interaction plays out, but there is
a growing signal for the potential of 3-5" (locally higher) of
rain somewhere over the lower MS Valley.

Chenard

...Previous Discussion...

The upper level low that was driving the heavy rainfall the
previous two days will move faster towards the northeast as it
continues its return to the jet stream over the northern tier of
states. The area will still have plenty of moisture from the Gulf
to work with as Rafael (or what's left of it) remains over the
central Gulf but the plume of moisture its embedded in continues to
be drawn north ahead of the surface low's strong cold front. The
front will likely be the dominant forcing for storms in this
region. As on Friday, the southern areas of Louisiana and
Mississippi will have the greater moisture and instability, while
further north FFGs are much lower due to recent heavy rainfall.
Thus, once again the Slight Risk is a two-fold combination of
factors that individually increase the flooding risk. The front
should still be slow enough moving that training storms tracking
north along the front could still cause flooding problems,
especially in Louisiana.

Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6QpVdzCGNJZel9efgSg4lDdB8oEZgBuYuMi6oRlGRpcE= 9qiPpExzPcJUVWs7cgm0OXhiRQlilN1bxLbgRE_STmahUsg$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6QpVdzCGNJZel9efgSg4lDdB8oEZgBuYuMi6oRlGRpcE= 9qiPpExzPcJUVWs7cgm0OXhiRQlilN1bxLbgRE_SPj-gnFQ$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6QpVdzCGNJZel9efgSg4lDdB8oEZgBuYuMi6oRlGRpcE= 9qiPpExzPcJUVWs7cgm0OXhiRQlilN1bxLbgRE_Sovm9tl0$=20

=3D =3D =3D
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FOUS30 KWBC 080758
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
258 AM EST Fri Nov 8 2024

Day 1
Valid 12Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

The upper level low over the Southwest and its attendant surface
low will continue moving northeast across the Plains on Friday.=20
With a continued influx of Gulf moisture with precipitable water
values of 1.5-2.25" expected near the cyclone's cold front, the=20
typical comma shaped precipitation footprint will develop farther
up the warm conveyor belt from Texas to Oklahoma which should occur
with precipitable water values at or above an inch. Out west in=20
Colorado and New Mexico the precipitation will be mostly in the=20
form of snow. Where it remains all rain, the heaviest rain will be=20
from north Texas across Oklahoma and into south-central Kansas.=20
Instability should be sufficient for heavy rain-related issues.

While somewhat lesser amounts of rain are expected overall for=20
southern Oklahoma and Texas...greater instability there as high as
1500 J/kg of MU CAPE will favor at least some storms capable of=20
heavy rainfall in that area, with hourly rain totals to 2.5" and=20
local amounts as high as 6" where cells train. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the=20
surface low takes its time getting its act together. So while=20
hourly rain totals will likely be lower than further south, perhaps
1" where slantwise convection/frontogenesis aloft forces greater=20 precipitation efficiency, it will be made up for by the longer=20
duration of the rain.

Roth/Wegman


Day 2
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE LOWER MISSISSIPPI VALLEY...

An upper level low will move faster towards the northeast. As=20
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the=20
surface low's strong cold front. The front will likely be the=20
dominant forcing for storms in this region. As on Friday, the=20
southern areas of Louisiana and Mississippi will have the greater=20
moisture. MU CAPE rises towards 1000 J/kg across parts of LA/MS/TN.
Areas further north have soils which are more saturated/flash=20
flood guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause=20
flooding problems, especially over portions of LA, MS, and TN.=20
Hourly rain totals to 2.5" and local amounts of around 6" appear=20
likely. Lingering disagreement on exactly where the maxima are=20
expected kept the risk level from being raised to Moderate, though=20
an upgrade remains possible in future updates should this placement
issue resolve itself and model QPF magnitudes don't back off.=20

Roth


Day 3
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...=20
AND UPPER OHIO VALLEY...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The latest NCEP=20
and CMC guidance suggests that Raphael gets much closer to the Gulf
Coast than the NHC forecast, which led to avoiding use of the GFS,
NAM, and Canadian guidance explicitly. Since the distance of the=20
storm from the region at this time frame is unclear, it's also=20
unclear how high precipitable water values get, though they should=20
rise above 1.5", particularly in the southern portion of the area
near the coast, which should be enough for heavy rain concerns. It
appears that enough instability could be available along the=20
immediate Gulf Coast for convection with heavy rainfall. Hourly=20
rain totals to 2" with local totals to 5" appear achievable along
or near the immediate Gulf coast. Whenever better agreement=20
amongst the guidance on the future of Rafael as well as the=20
placement any rainfall maximum near the coast occurs, a Slight=20
Risk could prove useful at that later time. To the north, hourly=20
totals up to ~1" with local totals to 2" appear to be the maximum=20
potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified=20
the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6okK3HoEyj5Taqk-KxSy7N4LRrsuqtLc9vmEddZ1h7wz= 1AQoFvzaPhyYqlwRJ1lD8otIAgvDyceTzzJ6FTvAa3GGHpE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6okK3HoEyj5Taqk-KxSy7N4LRrsuqtLc9vmEddZ1h7wz= 1AQoFvzaPhyYqlwRJ1lD8otIAgvDyceTzzJ6FTvAZqbGt0o$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6okK3HoEyj5Taqk-KxSy7N4LRrsuqtLc9vmEddZ1h7wz= 1AQoFvzaPhyYqlwRJ1lD8otIAgvDyceTzzJ6FTvAnK8OZQs$=20

=3D =3D =3D
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FOUS30 KWBC 081552
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1052 AM EST Fri Nov 8 2024

Day 1
Valid 16Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

...16z Update...

Little change needed for the 16z update, as the inherited Slight
Risk was maintained and adjusted a bit based on observational and=20
CAM trends. Much of the Slight Risk area (particularly the western
half) is on the lower-end of the probability spectrum, owning to
longer duration rainfall resulting in isolated to widely scattered
flash flooding. A good portion of the TX Hill Country has received
impressive 4-10" totals over the past 24 hours, resulting in highly
depressed FFGs with little additional rainfall needed to cause
problems. Even so, localized short-term totals going forward=20
should be capped around 1.5", greatly limiting the extent of any=20
additional flash flooding. Farther east into the Heart of TX=20
(mainly southeast of the Dallas-Fort Worth metro area), the Slight
Risk is considered to be on the higher-end of the probability=20
spectrum (25%+), as this region has the best chance of realizing=20
the highest rainfall rates (1-2"/hr) and resultant short-term=20
totals (20-30% odds of 5" exceedance, per 40-km neighborhood HREF=20 probabilities through 12z). Drier antecedent conditions in this=20
region should limit the extent and intensity of flash flooding=20
(with FFGs generally ranging from 3-4", coverage should remain=20
scattered and below significant flash flood thresholds).=20

Churchill


...Previous Discussion...

The upper level low over the Southwest and its attendant surface
low will continue moving northeast across the Plains on Friday.
With a continued influx of Gulf moisture with precipitable water
values of 1.5-2.25" expected near the cyclone's cold front, the
typical comma shaped precipitation footprint will develop farther
up the warm conveyor belt from Texas to Oklahoma which should occur
with precipitable water values at or above an inch. Out west in
Colorado and New Mexico the precipitation will be mostly in the
form of snow. Where it remains all rain, the heaviest rain will be
from north Texas across Oklahoma and into south-central Kansas.
Instability should be sufficient for heavy rain-related issues.

While somewhat lesser amounts of rain are expected overall for
southern Oklahoma and Texas...greater instability there as high as
1500 J/kg of MU CAPE will favor at least some storms capable of
heavy rainfall in that area, with hourly rain totals to 2.5" and
local amounts as high as 6" where cells train. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the
surface low takes its time getting its act together. So while
hourly rain totals will likely be lower than further south, perhaps
1" where slantwise convection/frontogenesis aloft forces greater
precipitation efficiency, it will be made up for by the longer
duration of the rain.

Roth/Wegman


Day 2
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE LOWER MISSISSIPPI VALLEY...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region. As on Friday, the
southern areas of Louisiana and Mississippi will have the greater
moisture. MU CAPE rises towards 1000 J/kg across parts of LA/MS/TN.
Areas further north have soils which are more saturated/flash
flood guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 6" appear
likely. Lingering disagreement on exactly where the maxima are
expected kept the risk level from being raised to Moderate, though
an upgrade remains possible in future updates should this placement
issue resolve itself and model QPF magnitudes don't back off.

Roth


Day 3
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The latest NCEP
and CMC guidance suggests that Raphael gets much closer to the Gulf
Coast than the NHC forecast, which led to avoiding use of the GFS,
NAM, and Canadian guidance explicitly. Since the distance of the
storm from the region at this time frame is unclear, it's also
unclear how high precipitable water values get, though they should
rise above 1.5", particularly in the southern portion of the area
near the coast, which should be enough for heavy rain concerns. It
appears that enough instability could be available along the
immediate Gulf Coast for convection with heavy rainfall. Hourly
rain totals to 2" with local totals to 5" appear achievable along
or near the immediate Gulf coast. Whenever better agreement
amongst the guidance on the future of Rafael as well as the
placement any rainfall maximum near the coast occurs, a Slight
Risk could prove useful at that later time. To the north, hourly
totals up to ~1" with local totals to 2" appear to be the maximum
potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6Y94yLOEn3MNhv7_LtFqaQW3Po2Y9AIvesfCL2J3ZYGq= XR_6yNL7cdyadh57h7N9EQaF__iyYY8R1LbjXc1ed2gqfs4$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6Y94yLOEn3MNhv7_LtFqaQW3Po2Y9AIvesfCL2J3ZYGq= XR_6yNL7cdyadh57h7N9EQaF__iyYY8R1LbjXc1e4kX4sbA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6Y94yLOEn3MNhv7_LtFqaQW3Po2Y9AIvesfCL2J3ZYGq= XR_6yNL7cdyadh57h7N9EQaF__iyYY8R1LbjXc1ex8Zc2hQ$=20

=3D =3D =3D
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FOUS30 KWBC 082002
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
302 PM EST Fri Nov 8 2024

Day 1
Valid 16Z Fri Nov 08 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

...16z Update...

Little change needed for the 16z update, as the inherited Slight
Risk was maintained and adjusted a bit based on observational and
CAM trends. Much of the Slight Risk area (particularly the western
half) is on the lower-end of the probability spectrum, owning to
longer duration rainfall resulting in isolated to widely scattered
flash flooding. A good portion of the TX Hill Country has received
impressive 4-10" totals over the past 24 hours, resulting in highly
depressed FFGs with little additional rainfall needed to cause
problems. Even so, localized short-term totals going forward
should be capped around 1.5", greatly limiting the extent of any
additional flash flooding. Farther east into the Heart of TX
(mainly southeast of the Dallas-Fort Worth metro area), the Slight
Risk is considered to be on the higher-end of the probability
spectrum (25%+), as this region has the best chance of realizing
the highest rainfall rates (1-2"/hr) and resultant short-term
totals (20-30% odds of 5" exceedance, per 40-km neighborhood HREF
probabilities through 12z). Drier antecedent conditions in this
region should limit the extent and intensity of flash flooding
(with FFGs generally ranging from 3-4", coverage should remain
scattered and below significant flash flood thresholds).

Churchill


...Previous Discussion...

The upper level low over the Southwest and its attendant surface
low will continue moving northeast across the Plains on Friday.
With a continued influx of Gulf moisture with precipitable water
values of 1.5-2.25" expected near the cyclone's cold front, the
typical comma shaped precipitation footprint will develop farther
up the warm conveyor belt from Texas to Oklahoma which should occur
with precipitable water values at or above an inch. Out west in
Colorado and New Mexico the precipitation will be mostly in the
form of snow. Where it remains all rain, the heaviest rain will be
from north Texas across Oklahoma and into south-central Kansas.
Instability should be sufficient for heavy rain-related issues.

While somewhat lesser amounts of rain are expected overall for
southern Oklahoma and Texas...greater instability there as high as
1500 J/kg of MU CAPE will favor at least some storms capable of
heavy rainfall in that area, with hourly rain totals to 2.5" and
local amounts as high as 6" where cells train. Meanwhile, north of
Oklahoma City, expect a much longer duration rainfall as the
surface low takes its time getting its act together. So while
hourly rain totals will likely be lower than further south, perhaps
1" where slantwise convection/frontogenesis aloft forces greater
precipitation efficiency, it will be made up for by the longer
duration of the rain.

Roth/Wegman


Day 2
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF=20
CENTRAL LOUISIANA...

20z Update: MDT risk upgrade across portions of central LA with
this update. Flash flooding is becoming increasingly likely across
this corridor, with locally significant impacts possible.=20
Favorable setup for heavy rainfall with moisture streaming north=20
from Rafael into the stalling front and upper jet. Global models=20
and HREF members are both showing a heavy rainfall threat in their
QPF as well. There remain some differences in the location of=20
heaviest rain, but generally seeing a consensus towards central LA.
We've got 3-5" of rain in the forecast, but there's a reasonable=20
possibility of localized 6-8" amounts. Some flash flooding is=20
possible Saturday morning, but an uptick in the coverage and=20
magnitude of impacts is expected during the afternoon and evening=20
hours.

Chenard

...Previous Discussion...=20

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region. As on Friday, the
southern areas of Louisiana and Mississippi will have the greater
moisture. MU CAPE rises towards 1000 J/kg across parts of LA/MS/TN.
Areas further north have soils which are more saturated/flash
flood guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 6" appear
likely. Lingering disagreement on exactly where the maxima are
expected kept the risk level from being raised to Moderate, though
an upgrade remains possible in future updates should this placement
issue resolve itself and model QPF magnitudes don't back off.

Roth


Day 3
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...

20z Update: No changes to the inherited Marginal risk areas, as
they still look in good shape. May eventually be able to trim back
the northern extent of the Marginal over PA/OH/WV given the dry=20
soil conditions and lack of instability...but will maintain=20
continuity for now with PWs forecast 2-3 SD above average and=20
decent forcing in place.

Chenard

...Previous Discussion...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The latest NCEP
and CMC guidance suggests that Raphael gets much closer to the Gulf
Coast than the NHC forecast, which led to avoiding use of the GFS,
NAM, and Canadian guidance explicitly. Since the distance of the
storm from the region at this time frame is unclear, it's also
unclear how high precipitable water values get, though they should
rise above 1.5", particularly in the southern portion of the area
near the coast, which should be enough for heavy rain concerns. It
appears that enough instability could be available along the
immediate Gulf Coast for convection with heavy rainfall. Hourly
rain totals to 2" with local totals to 5" appear achievable along
or near the immediate Gulf coast. Whenever better agreement
amongst the guidance on the future of Rafael as well as the
placement any rainfall maximum near the coast occurs, a Slight
Risk could prove useful at that later time. To the north, hourly
totals up to ~1" with local totals to 2" appear to be the maximum
potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!9JMcRCb1ZG8l_gz9OQIkogXeUM24RT0ZiFIx_g8f7wPS= IExsJsgMS2zzIXXmAR2Qnc99KPb9TxNv77hBtPZ3ltWH8T8$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!9JMcRCb1ZG8l_gz9OQIkogXeUM24RT0ZiFIx_g8f7wPS= IExsJsgMS2zzIXXmAR2Qnc99KPb9TxNv77hBtPZ3wFi8vKo$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!9JMcRCb1ZG8l_gz9OQIkogXeUM24RT0ZiFIx_g8f7wPS= IExsJsgMS2zzIXXmAR2Qnc99KPb9TxNv77hBtPZ3RBj28gc$=20

=3D =3D =3D
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FOUS30 KWBC 090017
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
717 PM EST Fri Nov 8 2024

Day 1
Valid 01Z Sat Nov 09 2024 - 12Z Sat Nov 09 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHERN PLAINS...

...16z Update...

Little change needed for the 01Z update...with the biggest changes
resulting from adjustments to better fit early evening radar and
satellite imagery and latest CAM trends. Much of the western part
of the Slight Risk was removed as cooler and drier air sweeps
eastward behind a steadily progressive cold front.=20

Early evening radar showed several lines of showers and=20
thunderstorms were still poised to cross the Slight Risk area this=20
evening and overnight...where a 25 to 35 kt low level jet continued
to tap deeper moisture from the Gulf of Mexico and established an
axis of precipitable water values exceeding 1.75 inches that
extended across eastern Texas into portions of eastern Oklahoma and
nearby Louisiana and Arkansas. In this area...the Slight Risk is=20
considered to be on the higher- end of the probability spectrum=20
(25%+), as this region has the best chance of realizing the highest
rainfall rates (1-2"/hr) and resultant short- term totals (20-30%=20
odds of 5" exceedance, per 40-km neighborhood HREF probabilities=20
through 09/12Z). Drier antecedent conditions in this region should=20
limit the extent and intensity of flash flooding (with FFGs=20
generally ranging from 3-4", coverage should remain scattered and=20
below significant flash flood thresholds).

Bann


Day 2
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
CENTRAL LOUISIANA...

20z Update: MDT risk upgrade across portions of central LA with
this update. Flash flooding is becoming increasingly likely across
this corridor, with locally significant impacts possible.
Favorable setup for heavy rainfall with moisture streaming north
from Rafael into the stalling front and upper jet. Global models
and HREF members are both showing a heavy rainfall threat in their
QPF as well. There remain some differences in the location of
heaviest rain, but generally seeing a consensus towards central LA.
We've got 3-5" of rain in the forecast, but there's a reasonable
possibility of localized 6-8" amounts. Some flash flooding is
possible Saturday morning, but an uptick in the coverage and
magnitude of impacts is expected during the afternoon and evening
hours.

Chenard

...Previous Discussion...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region. As on Friday, the
southern areas of Louisiana and Mississippi will have the greater
moisture. MU CAPE rises towards 1000 J/kg across parts of LA/MS/TN.
Areas further north have soils which are more saturated/flash
flood guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 6" appear
likely. Lingering disagreement on exactly where the maxima are
expected kept the risk level from being raised to Moderate, though
an upgrade remains possible in future updates should this placement
issue resolve itself and model QPF magnitudes don't back off.

Roth


Day 3
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...

20z Update: No changes to the inherited Marginal risk areas, as
they still look in good shape. May eventually be able to trim back
the northern extent of the Marginal over PA/OH/WV given the dry
soil conditions and lack of instability...but will maintain
continuity for now with PWs forecast 2-3 SD above average and
decent forcing in place.

Chenard

...Previous Discussion...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The latest NCEP
and CMC guidance suggests that Raphael gets much closer to the Gulf
Coast than the NHC forecast, which led to avoiding use of the GFS,
NAM, and Canadian guidance explicitly. Since the distance of the
storm from the region at this time frame is unclear, it's also
unclear how high precipitable water values get, though they should
rise above 1.5", particularly in the southern portion of the area
near the coast, which should be enough for heavy rain concerns. It
appears that enough instability could be available along the
immediate Gulf Coast for convection with heavy rainfall. Hourly
rain totals to 2" with local totals to 5" appear achievable along
or near the immediate Gulf coast. Whenever better agreement
amongst the guidance on the future of Rafael as well as the
placement any rainfall maximum near the coast occurs, a Slight
Risk could prove useful at that later time. To the north, hourly
totals up to ~1" with local totals to 2" appear to be the maximum
potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_BmXW38OVE_2Fy8jgwwwbUplgRaVOsegIc6eSmO1bsfY= g-ai0IxCYLOwvBjkkickJgaBK1XBUpFxHSIKoLlC2AYWzqA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_BmXW38OVE_2Fy8jgwwwbUplgRaVOsegIc6eSmO1bsfY= g-ai0IxCYLOwvBjkkickJgaBK1XBUpFxHSIKoLlCUIgBNM0$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_BmXW38OVE_2Fy8jgwwwbUplgRaVOsegIc6eSmO1bsfY= g-ai0IxCYLOwvBjkkickJgaBK1XBUpFxHSIKoLlCMeZSMwc$=20

=3D =3D =3D
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FOUS30 KWBC 090741
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
241 AM EST Sat Nov 9 2024

Day 1
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL IN AND NEAR IMPERIAL
CALCASIEU IN LOUISIANA...

An upper level low will move faster towards the northeast. As=20
Rafael moves west over the central Gulf, a plume of moisture with=20 precipitable water values of 1.5-2" gets drawn north ahead of the=20
surface low's strong cold front. The front will likely be the=20
dominant forcing for storms in this region as it stalls, which have
already begun to evolve in recent radar imagery. The southern=20
areas of Louisiana and Mississippi will have the greater moisture.=20
MU CAPE rises to 1000 J/kg or so across parts of LA/MS/TN. Areas=20
further north have soils which are more saturated/flash flood=20
guidance is lower. The front should progress slow enough that=20
training storms tracking north along the front could still cause=20
flooding problems, especially over portions of LA, MS, and TN.=20
Hourly rain totals to 2.5" and local amounts of around 8" appear=20
likely based on the 00z HREF probabilities of 8" totals. There is=20
much better agreement on the placement when compared to this time=20
yesterday. Portions of Central LA have received 300%+ of their=20
average seven day rainfall, so soils should have some sensitivity.=20 Coordination with the LCH/Lake Charles LA forecast office led to
the Local impacts more aligned with a High Risk cannot be ruled=20
out.

Roth


Day 2
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...

20z Update: No changes to the inherited Marginal risk areas, as
they still look in good shape. May eventually be able to trim back
the northern extent of the Marginal over PA/OH/WV given the dry
soil conditions and lack of instability...but will maintain
continuity for now with PWs forecast 2-3 SD above average and
decent forcing in place.

Chenard

...Previous Discussion...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The latest NCEP
and CMC guidance suggests that Raphael gets much closer to the Gulf
Coast than the NHC forecast, which led to avoiding use of the GFS,
NAM, and Canadian guidance explicitly. Since the distance of the
storm from the region at this time frame is unclear, it's also
unclear how high precipitable water values get, though they should
rise above 1.5", particularly in the southern portion of the area
near the coast, which should be enough for heavy rain concerns. It
appears that enough instability could be available along the
immediate Gulf Coast for convection with heavy rainfall. Hourly
rain totals to 2" with local totals to 5" appear achievable along
or near the immediate Gulf coast. Whenever better agreement
amongst the guidance on the future of Rafael as well as the
placement any rainfall maximum near the coast occurs, a Slight
Risk could prove useful at that later time. To the north, hourly
totals up to ~1" with local totals to 2" appear to be the maximum
potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 3
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST & CENTRAL GULF COAST...

Central Gulf Coast...
Precipitable water values north of Rafael are expected to remain in
the 1.5-2" range in the vicinity of a slowly progressive front near
the Central Gulf Coast. While much of the guidance keeps rainfall=20
amounts minimal, the 00z NAM showed local amounts of 3"+, though=20
it gets there by allowing Rafael to get much closer to the Gulf=20
Coast than other model guidance. Considering that heavy rainfall=20
is possible over the previous couple of days, figured a new=20
Marginal Risk was a sensible precaution in case the NAM is close to
correct and/or soils are saturated by that time.


Pacific Northwest...
Precipitable water values of 0.5-0.75" and MU CAPE of a few hundred
J/kg are expected in a post-frontal environment. Inflow off the
Pacific is expected to remain around 40 kts. Hourly rain totals=20
exceeding 0.5" remain possible, which would be most problematic in
burn scars. Left the inherited Marginal Risk area intact though=20
simplified the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_q0bgt76RfSt6bPhlpK5fJYf1gR4Fm94zzW1VAjDC5ze= NipEeRN0eg1VuV8ktpUJ8bKgisdfWXvmDWaK_lJTUO3VRFo$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_q0bgt76RfSt6bPhlpK5fJYf1gR4Fm94zzW1VAjDC5ze= NipEeRN0eg1VuV8ktpUJ8bKgisdfWXvmDWaK_lJTLgl3Fyw$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_q0bgt76RfSt6bPhlpK5fJYf1gR4Fm94zzW1VAjDC5ze= NipEeRN0eg1VuV8ktpUJ8bKgisdfWXvmDWaK_lJTSsuTGgs$=20

=3D =3D =3D
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FOUS30 KWBC 090743
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
243 AM EST Sat Nov 9 2024

Day 1
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL IN AND NEAR IMPERIAL
CALCASIEU IN LOUISIANA...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region as it stalls, which have
already begun to evolve in recent radar imagery. The southern
areas of Louisiana and Mississippi will have the greater moisture.
MU CAPE rises to 1000 J/kg or so across parts of LA/MS/TN. Areas
further north have soils which are more saturated/flash flood
guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 8" due to
cell training appear likely based on the 00z HREF probabilities of
8" totals. There is much better agreement on the placement when=20
compared to this time yesterday. Portions of Central LA have=20
received 300%+ of their average seven day rainfall, so soils should
have some sensitivity. Coordination with the LCH/Lake Charles LA=20
forecast office led to the increase to a High Risk.

Roth


Day 2
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...

20z Update: No changes to the inherited Marginal risk areas, as
they still look in good shape. May eventually be able to trim back
the northern extent of the Marginal over PA/OH/WV given the dry
soil conditions and lack of instability...but will maintain
continuity for now with PWs forecast 2-3 SD above average and
decent forcing in place.

Chenard

...Previous Discussion...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The latest NCEP
and CMC guidance suggests that Raphael gets much closer to the Gulf
Coast than the NHC forecast, which led to avoiding use of the GFS,
NAM, and Canadian guidance explicitly. Since the distance of the
storm from the region at this time frame is unclear, it's also
unclear how high precipitable water values get, though they should
rise above 1.5", particularly in the southern portion of the area
near the coast, which should be enough for heavy rain concerns. It
appears that enough instability could be available along the
immediate Gulf Coast for convection with heavy rainfall. Hourly
rain totals to 2" with local totals to 5" appear achievable along
or near the immediate Gulf coast. Whenever better agreement
amongst the guidance on the future of Rafael as well as the
placement any rainfall maximum near the coast occurs, a Slight
Risk could prove useful at that later time. To the north, hourly
totals up to ~1" with local totals to 2" appear to be the maximum
potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 3
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST & CENTRAL GULF COAST...

Central Gulf Coast...
Precipitable water values north of Rafael are expected to remain in
the 1.5-2" range in the vicinity of a slowly progressive front near
the Central Gulf Coast. While much of the guidance keeps rainfall
amounts minimal, the 00z NAM showed local amounts of 3"+, though
it gets there by allowing Rafael to get much closer to the Gulf
Coast than other model guidance. Considering that heavy rainfall
is possible over the previous couple of days, figured a new
Marginal Risk was a sensible precaution in case the NAM is close to
correct and/or soils are saturated by that time.


Pacific Northwest...
Precipitable water values of 0.5-0.75" and MU CAPE of a few hundred
J/kg are expected in a post-frontal environment. Inflow off the
Pacific is expected to remain around 40 kts. Hourly rain totals
exceeding 0.5" remain possible, which would be most problematic in
burn scars. Left the inherited Marginal Risk area intact though
simplified the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-cAIEITF4KL0agWdRoJqAUqChqAkOdPdmh9S-Jvu7-3N= h_VwwUe-U7Ew9HjgX9wWSjWyLN4Cw8D6fcXtjXh0w6GlzGA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-cAIEITF4KL0agWdRoJqAUqChqAkOdPdmh9S-Jvu7-3N= h_VwwUe-U7Ew9HjgX9wWSjWyLN4Cw8D6fcXtjXh0XWMvpvI$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-cAIEITF4KL0agWdRoJqAUqChqAkOdPdmh9S-Jvu7-3N= h_VwwUe-U7Ew9HjgX9wWSjWyLN4Cw8D6fcXtjXh0FAQR_II$=20

=3D =3D =3D
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FOUS30 KWBC 090748
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
248 AM EST Sat Nov 9 2024

Day 1
Valid 12Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL IN AND NEAR IMPERIAL
CALCASIEU IN LOUISIANA...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region as it stalls, which have
already begun to evolve in recent radar imagery. The southern
areas of Louisiana and Mississippi will have the greater moisture.
MU CAPE rises to 1000 J/kg or so across parts of LA/MS/TN. Areas
further north have soils which are more saturated/flash flood
guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 8" due to
cell training appear likely based on the 00z HREF probabilities of
8" totals. There is much better agreement on the placement when
compared to this time yesterday. Portions of Central LA have
received 300%+ of their average seven day rainfall, so soils should
have some sensitivity. Coordination with the LCH/Lake Charles LA
forecast office led to the increase to a High Risk.

Roth


Day 2
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...


Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The guidance
remains unclear as to whether heavy rainfall gets ashore or not.
Precipitable water values should rise above 1.5", particularly in=20
the southern portion of the area near the coast, which should be=20
enough for heavy rain concerns. It appears that enough instability=20
could be available along the immediate Gulf Coast for convection=20
with heavy rainfall. Hourly rain totals to 2" with local totals to=20
5" appear achievable along or near the immediate Gulf coast.=20
Whenever better agreement amongst the guidance on the future of=20
Rafael as well as the placement any rainfall maximum near the coast
occurs, a Slight Risk could prove useful at that later time. To=20
the north, hourly totals up to ~1" with local totals to 2" appear=20
to be the maximum potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 3
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST & CENTRAL GULF COAST...

Central Gulf Coast...
Precipitable water values north of Rafael are expected to remain in
the 1.5-2" range in the vicinity of a slowly progressive front near
the Central Gulf Coast. While much of the guidance keeps rainfall
amounts minimal, the 00z NAM showed local amounts of 3"+, though
it gets there by allowing Rafael to get much closer to the Gulf
Coast than other model guidance. Considering that heavy rainfall
is possible over the previous couple of days, figured a new
Marginal Risk was a sensible precaution in case the NAM is close to
correct and/or soils are saturated by that time.


Pacific Northwest...
Precipitable water values of 0.5-0.75" and MU CAPE of a few hundred
J/kg are expected in a post-frontal environment. Inflow off the
Pacific is expected to remain around 40 kts. Hourly rain totals
exceeding 0.5" remain possible, which would be most problematic in
burn scars. Left the inherited Marginal Risk area intact though
simplified the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-6BqCTwi2BmPOduFOSKXHpd4HUbEUFdsdvm-KfDeFnzr= nhFBEJKIz16U-Ao5V_CV_kLT03yMiaTiUw0JvJaDIgt32mE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-6BqCTwi2BmPOduFOSKXHpd4HUbEUFdsdvm-KfDeFnzr= nhFBEJKIz16U-Ao5V_CV_kLT03yMiaTiUw0JvJaDHEP1Ijg$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-6BqCTwi2BmPOduFOSKXHpd4HUbEUFdsdvm-KfDeFnzr= nhFBEJKIz16U-Ao5V_CV_kLT03yMiaTiUw0JvJaDY1_U86w$=20

=3D =3D =3D
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FOUS30 KWBC 091600
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1100 AM EST Sat Nov 9 2024

Day 1
Valid 16Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL IN AND NEAR IMPERIAL
CALCASIEU IN LOUISIANA...

...16z Update...

Little changes needed for this update, as the new suite of 12z CAMs
remain supportive of relatively small High Risk over southwestern=20
and central portions of LA. HREF 40-km neighborhood probabilities
for 8" exceedance remain high (between 40-80%), with 100-yr ARI
exceedance probabilities as high as 30-40%. The deep tropical=20
moisture ushered in as a result of Tropical Storm Rafael is more=20
typical of late August to early September with precipitable water=20
values near 2.2" (well above the 90th percentile and near record=20
levels for early November, per LCH sounding climatology). See MPD=20
#1145 (and subsequent MPDs) for more information on the near term
threat. Only relatively minor adjustments to the Slight, Moderate,
and High Risk contours for this update (based on the latest trends).

Churchill


...Previous Discussion...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region as it stalls, which have
already begun to evolve in recent radar imagery. The southern
areas of Louisiana and Mississippi will have the greater moisture.
MU CAPE rises to 1000 J/kg or so across parts of LA/MS/TN. Areas
further north have soils which are more saturated/flash flood
guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 8" due to
cell training appear likely based on the 00z HREF probabilities of
8" totals. There is much better agreement on the placement when
compared to this time yesterday. Portions of Central LA have
received 300%+ of their average seven day rainfall, so soils should
have some sensitivity. Coordination with the LCH/Lake Charles LA
forecast office led to the increase to a High Risk.

Roth


Day 2
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST, LOWER MISSISSIPPI VALLEY...TENNESSEE VALLEY...
AND UPPER OHIO VALLEY...


Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The guidance
remains unclear as to whether heavy rainfall gets ashore or not.
Precipitable water values should rise above 1.5", particularly in
the southern portion of the area near the coast, which should be
enough for heavy rain concerns. It appears that enough instability
could be available along the immediate Gulf Coast for convection
with heavy rainfall. Hourly rain totals to 2" with local totals to
5" appear achievable along or near the immediate Gulf coast.
Whenever better agreement amongst the guidance on the future of
Rafael as well as the placement any rainfall maximum near the coast
occurs, a Slight Risk could prove useful at that later time. To
the north, hourly totals up to ~1" with local totals to 2" appear
to be the maximum potential.


Pacific Northwest...
Precipitable water values rise to 0.75-1" with a front moving into
the area. Inflow from the Pacific rises to 50-60 kts from the
south-southwest near the front. In the wake of the front,
instability moves in due to colder air aloft. Hourly rain totals
exceeding 0.5" appear likely here, which would be most problematic
in burn scars. Left the Marginal Risk area intact though simplified
the area's appearance.

Roth


Day 3
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
PACIFIC NORTHWEST & CENTRAL GULF COAST...

Central Gulf Coast...
Precipitable water values north of Rafael are expected to remain in
the 1.5-2" range in the vicinity of a slowly progressive front near
the Central Gulf Coast. While much of the guidance keeps rainfall
amounts minimal, the 00z NAM showed local amounts of 3"+, though
it gets there by allowing Rafael to get much closer to the Gulf
Coast than other model guidance. Considering that heavy rainfall
is possible over the previous couple of days, figured a new
Marginal Risk was a sensible precaution in case the NAM is close to
correct and/or soils are saturated by that time.


Pacific Northwest...
Precipitable water values of 0.5-0.75" and MU CAPE of a few hundred
J/kg are expected in a post-frontal environment. Inflow off the
Pacific is expected to remain around 40 kts. Hourly rain totals
exceeding 0.5" remain possible, which would be most problematic in
burn scars. Left the inherited Marginal Risk area intact though
simplified the area's appearance.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5_b3nzmtBS9-ADvwFBv0yS82zsfkPArX_KsAbUXLKW9K= a-zQW5ilFuX0HcuOj8QzzbghuS-xBFCoXVA4znAOQOiXflA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5_b3nzmtBS9-ADvwFBv0yS82zsfkPArX_KsAbUXLKW9K= a-zQW5ilFuX0HcuOj8QzzbghuS-xBFCoXVA4znAOB9XQoVY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5_b3nzmtBS9-ADvwFBv0yS82zsfkPArX_KsAbUXLKW9K= a-zQW5ilFuX0HcuOj8QzzbghuS-xBFCoXVA4znAOKZNDeK4$=20

=3D =3D =3D
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FOUS30 KWBC 091922
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
222 PM EST Sat Nov 9 2024

Day 1
Valid 16Z Sat Nov 09 2024 - 12Z Sun Nov 10 2024

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL IN AND NEAR IMPERIAL
CALCASIEU IN LOUISIANA...

...16z Update...

Little changes needed for this update, as the new suite of 12z CAMs
remain supportive of relatively small High Risk over southwestern
and central portions of LA. HREF 40-km neighborhood probabilities
for 8" exceedance remain high (between 40-80%), with 100-yr ARI
exceedance probabilities as high as 30-40%. The deep tropical
moisture ushered in as a result of Tropical Storm Rafael is more
typical of late August to early September with precipitable water
values near 2.2" (well above the 90th percentile and near record
levels for early November, per LCH sounding climatology). See MPD
#1145 (and subsequent MPDs) for more information on the near term
threat. Only relatively minor adjustments to the Slight, Moderate,
and High Risk contours for this update (based on the latest trends).

Churchill


...Previous Discussion...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region as it stalls, which have
already begun to evolve in recent radar imagery. The southern
areas of Louisiana and Mississippi will have the greater moisture.
MU CAPE rises to 1000 J/kg or so across parts of LA/MS/TN. Areas
further north have soils which are more saturated/flash flood
guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 8" due to
cell training appear likely based on the 00z HREF probabilities of
8" totals. There is much better agreement on the placement when
compared to this time yesterday. Portions of Central LA have
received 300%+ of their average seven day rainfall, so soils should
have some sensitivity. Coordination with the LCH/Lake Charles LA
forecast office led to the increase to a High Risk.

Roth


Day 2
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSISSIPPI VALLEY AND TENNESSEE VALLEY...

20z Update: A Marginal risk was maintained from the central Gulf
Coast northeastward into KY. Flash flooding may be ongoing at 12z
Sunday across portions of LA, although guidance indicates
convection should be on a weakening trend by late tonight into the
morning hours. At the moment our post 12z QPF does not support=20
anything more than a Marginal risk over LA, however given what=20
should be saturated conditions after todays and tonight's rainfall,
if convection is persisting longer than forecast than an upgrade=20
in the ERO may be needed through Sunday morning. We were able to=20
trim back the northeastern portion of the risk area over PA/OH/WV.=20
While QPF of 1-1.5" is still forecast, limited instability should=20
keep rainfall rates below 0.5" in an hour over these areas. Not=20
seeing any FFG exceedance probabilities in the HREF given these=20
weaker expected rates and dry antecedent conditions.

The Marginal risk over the Pacific Northwest was removed with this
update. The front Sunday night into Monday morning is expected to
be progressive in nature limiting rainfall totals and impacts. Some
brief 0.5" per hour rates are possible along the OR coast, but the
quick movement should limit impacts. All the impacted WFOs were in
agreement on dropping the risk.

Chenard

...Previous Discussion...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The guidance
remains unclear as to whether heavy rainfall gets ashore or not.
Precipitable water values should rise above 1.5", particularly in
the southern portion of the area near the coast, which should be
enough for heavy rain concerns. It appears that enough instability
could be available along the immediate Gulf Coast for convection
with heavy rainfall. Hourly rain totals to 2" with local totals to
5" appear achievable along or near the immediate Gulf coast.
Whenever better agreement amongst the guidance on the future of
Rafael as well as the placement any rainfall maximum near the coast
occurs, a Slight Risk could prove useful at that later time. To
the north, hourly totals up to ~1" with local totals to 2" appear
to be the maximum potential.

Roth


Day 3
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

The Gulf Coast Marginal was dropped as rainfall intensity/coverage
should be decreasing by this time. Still a non-zero chance of a=20
localized flash flood near the coast, however the latest=20
deterministic and ensemble guidance suggests FFG exceedance chances
are too low to justify an area at this time.

The Marginal over the Western U.S. was also dropped in coordination
with impacted local WFOs. The first system will exit the area=20
Monday morning, with just post frontal showery conditions expected
behind it through Tuesday morning. While weak instability behind=20
the front may support some briefly heavy rates, the coverage and=20
duration of any heavier rainfall should be too short to cause=20
impacts with antecedent soil and streamflows running either=20
average or below average for early November. This rainfall will
help increase saturation ahead of the day 4/5 atmospheric=20
river...which is expected to be a stronger and more persistent=20
system. Thus Marginal risks will continue for the day 4 and 5=20
period.

Chenard


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!7iVlQ7pIN9j83i7AeordWIUYh5OAppk7qdCKm_lAK4jW= hfhyNiVd5g8BzlRa-yoMPnOqva09f1LabHxtYGkhfR8YcrA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!7iVlQ7pIN9j83i7AeordWIUYh5OAppk7qdCKm_lAK4jW= hfhyNiVd5g8BzlRa-yoMPnOqva09f1LabHxtYGkh07ao45s$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!7iVlQ7pIN9j83i7AeordWIUYh5OAppk7qdCKm_lAK4jW= hfhyNiVd5g8BzlRa-yoMPnOqva09f1LabHxtYGkhByp_ub0$=20

=3D =3D =3D
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FOUS30 KWBC 100031
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
731 PM EST Sat Nov 9 2024

Day 1
Valid 01Z Sun Nov 10 2024 - 12Z Sun Nov 10 2024

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL IN AND NEAR IMPERIAL
CALCASIEU IN LOUISIANA...

...01Z Update...
Little change needed again for this update with on-going moderate
to heavy rainfall still occurring over the central and=20
southwestern Louisiana. In addition...MRMS radar QPE combined with=20
the CAM QPF/neighborhood probabilities still remain supportive the=20
on-going outlook. Expanded some of the lower-end outlook categories northeastward in Louisiana where rainfall earlier today led to=20
increasingly saturated soils...and roughly corresponds to the same=20
area as the National Water Center's Area Hydrologic Discussion 305=20
valid through the remainder of the ERO Day 1 period. There are=20
signals from the HREF and HRRR that rainfall rates will be tapering
off overnight...but convergent low level flow of two moist streams
seen on satellite and radar early this evening flowinng into
southwesternb Louisiana point to it being too early to make any=20
wholesale changes to the on-going Moderate or High risk.

Bann

...16z Update...

Little changes needed for this update, as the new suite of 12z CAMs
remain supportive of relatively small High Risk over southwestern
and central portions of LA. HREF 40-km neighborhood probabilities
for 8" exceedance remain high (between 40-80%), with 100-yr ARI
exceedance probabilities as high as 30-40%. The deep tropical
moisture ushered in as a result of Tropical Storm Rafael is more
typical of late August to early September with precipitable water
values near 2.2" (well above the 90th percentile and near record
levels for early November, per LCH sounding climatology). See MPD
#1145 (and subsequent MPDs) for more information on the near term
threat. Only relatively minor adjustments to the Slight, Moderate,
and High Risk contours for this update (based on the latest trends).

Churchill


...Previous Discussion...

An upper level low will move faster towards the northeast. As
Rafael moves west over the central Gulf, a plume of moisture with
precipitable water values of 1.5-2" gets drawn north ahead of the
surface low's strong cold front. The front will likely be the
dominant forcing for storms in this region as it stalls, which have
already begun to evolve in recent radar imagery. The southern
areas of Louisiana and Mississippi will have the greater moisture.
MU CAPE rises to 1000 J/kg or so across parts of LA/MS/TN. Areas
further north have soils which are more saturated/flash flood
guidance is lower. The front should progress slow enough that
training storms tracking north along the front could still cause
flooding problems, especially over portions of LA, MS, and TN.
Hourly rain totals to 2.5" and local amounts of around 8" due to
cell training appear likely based on the 00z HREF probabilities of
8" totals. There is much better agreement on the placement when
compared to this time yesterday. Portions of Central LA have
received 300%+ of their average seven day rainfall, so soils should
have some sensitivity. Coordination with the LCH/Lake Charles LA
forecast office led to the increase to a High Risk.

Roth


Day 2
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSISSIPPI VALLEY AND TENNESSEE VALLEY...

20z Update: A Marginal risk was maintained from the central Gulf
Coast northeastward into KY. Flash flooding may be ongoing at 12z
Sunday across portions of LA, although guidance indicates
convection should be on a weakening trend by late tonight into the
morning hours. At the moment our post 12z QPF does not support
anything more than a Marginal risk over LA, however given what
should be saturated conditions after todays and tonight's rainfall,
if convection is persisting longer than forecast than an upgrade
in the ERO may be needed through Sunday morning. We were able to
trim back the northeastern portion of the risk area over PA/OH/WV.
While QPF of 1-1.5" is still forecast, limited instability should
keep rainfall rates below 0.5" in an hour over these areas. Not
seeing any FFG exceedance probabilities in the HREF given these
weaker expected rates and dry antecedent conditions.

The Marginal risk over the Pacific Northwest was removed with this
update. The front Sunday night into Monday morning is expected to
be progressive in nature limiting rainfall totals and impacts. Some
brief 0.5" per hour rates are possible along the OR coast, but the
quick movement should limit impacts. All the impacted WFOs were in
agreement on dropping the risk.

Chenard

...Previous Discussion...

Central Gulf Coast northeast towards southwest Pennsylvania...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northeast across portions of the Central Gulf
Coast through the Tennessee and Upper Ohio Valleys. The forward
progress of the front across much of the East should keep any
excessive rainfall concerns minimal -- some of the risk area from
eastern AR to the east-northeast just south of the OH river
accounts for recent rains/some soil saturation. The guidance
remains unclear as to whether heavy rainfall gets ashore or not.
Precipitable water values should rise above 1.5", particularly in
the southern portion of the area near the coast, which should be
enough for heavy rain concerns. It appears that enough instability
could be available along the immediate Gulf Coast for convection
with heavy rainfall. Hourly rain totals to 2" with local totals to
5" appear achievable along or near the immediate Gulf coast.
Whenever better agreement amongst the guidance on the future of
Rafael as well as the placement any rainfall maximum near the coast
occurs, a Slight Risk could prove useful at that later time. To
the north, hourly totals up to ~1" with local totals to 2" appear
to be the maximum potential.

Roth


Day 3
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

The Gulf Coast Marginal was dropped as rainfall intensity/coverage
should be decreasing by this time. Still a non-zero chance of a
localized flash flood near the coast, however the latest
deterministic and ensemble guidance suggests FFG exceedance chances
are too low to justify an area at this time.

The Marginal over the Western U.S. was also dropped in coordination
with impacted local WFOs. The first system will exit the area
Monday morning, with just post frontal showery conditions expected
behind it through Tuesday morning. While weak instability behind
the front may support some briefly heavy rates, the coverage and
duration of any heavier rainfall should be too short to cause
impacts with antecedent soil and streamflows running either
average or below average for early November. This rainfall will
help increase saturation ahead of the day 4/5 atmospheric
river...which is expected to be a stronger and more persistent
system. Thus Marginal risks will continue for the day 4 and 5
period.

Chenard


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4AdaDQG-Q7xgb8eyYRQTMZ4DlsByx9m3-yz6Rl_RejxY= XEXur5XsdLFlo43UisqYuGXvVf2sEaQRt7yXTH42Ph5ipFA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4AdaDQG-Q7xgb8eyYRQTMZ4DlsByx9m3-yz6Rl_RejxY= XEXur5XsdLFlo43UisqYuGXvVf2sEaQRt7yXTH42xjei6oU$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4AdaDQG-Q7xgb8eyYRQTMZ4DlsByx9m3-yz6Rl_RejxY= XEXur5XsdLFlo43UisqYuGXvVf2sEaQRt7yXTH42ETjlI6U$=20

=3D =3D =3D
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FOUS30 KWBC 100814
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
314 AM EST Sun Nov 10 2024

Day 1
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS CENTRAL AND
SOUTHWEST LOUISIANA...

Southwest and Central Louisiana...=20
Moisture and instability from the Gulf gets advected from the=20
vicinity of Raphael northwest to north across portions of the=20
Central Gulf Coast through the Tennessee Valley. A slowly=20
advancing convective complex early this morning across southwest LA
is drifting eastward, showing hourly rain totals to 3" and=20
isolated totals to 13" thus far over portions of Allen Parish.=20
There is concern that this complex could hold together past 12z,=20
which is part of the reason for the upgrade to a Slight Risk, after coordinating with the LCH/Lake Charles LA forecast office.=20
Additional activity could form behind it closer to a surface=20
boundary in TX (could be forming at the present time) which is=20
expected to advect eastward during daytime heating. Moderate Risk=20
level impacts cannot be ruled out should such thunderstorm activity
persist over recently saturated soils into this afternoon.


Southeast Louisiana...
The guidance broadly remains unclear as to whether heavy rainfall=20
gets too far ashore southeast LA while mesoscale guidance shows the
complex to the west fizzling as it moves into the region.=20
Precipitable water values of 1.5-2" Sunday morning across southeast
LA advect offshore with time, which should limit heavy rainfall=20
concerns. Still, hourly rain totals to 2" and local totals to 4"=20
are possible on an isolated basis should storms backbuild or train.



Interior Southeast/Mid-South/Tennessee Valley...=20
The forward progress of the front should keep any excessive=20
rainfall concerns minimal in areas a bit north of the Gulf Coast=20
-- some of the risk area from eastern AR to the east-northeast just
south of the OH river accounts for recent rains/some soil=20
saturation. In this more northern portion of the Marginal Risk=20
area, hourly totals up to ~1" with local totals to 2" appear to be
the maximum potential. A decent amount of the area within the=20
Marginal Risk would find the forecasted rainfall welcome.

Changes to continuity were to shave off some of the northeast=20
portion of the Marginal Risk area, using 00z HREF probabilities of=20
0.5"+ as a guide, and include some of far southeast Texas to=20
account for the limited QPF signal there as soils are a bit more=20
sensitive after the past 24-36 hours of heavy rainfall. Central and
Southeast LA remain within the Marginal Risk for similar reasons,=20
concerns about locally heavy rains over saturated soils from recent
heavy rain. The 00z HREF had low, but existent, probabilities of
3"+ during the day 1/Sunday morning into early Monday time frame.

Roth


Day 2
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Roth


Day 3
Valid 12Z Tue Nov 12 2024 - 12Z Wed Nov 13 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN AND NEAR
WESTERN WASHINGTON...

Precipitable water values of 0.75-1" advect in as a cold front=20
approaches, perhaps moves ashore, the Washington and northern
Oregon coast Wednesday morning. Inflow from the Pacific rises to=20
60 kts at 850 hPa out of the south-southwest with limited=20
instability available near and behind the front. The ingredients=20
appear to be there for hourly rain totals of 0.5"+, which would be
most problematic in burn scars. Over the full day, local amounts=20
of 3-4" are advertised for much of the guidance, which would be=20
most problematic along the Skokomish river in the Olympic=20
Peninsula. Enough was there in the guidance for the inherited=20
Marginal Risk area to remain from continuity; simplified its shape.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8c-A0rdsMNZHVCH_SQet2G_MU0xkzZQqC_u6LIHna_FO= UNqMq6sJ_nc0OXQLdtHhXqhkptLrti1E36fdzEIjQq_mAkw$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8c-A0rdsMNZHVCH_SQet2G_MU0xkzZQqC_u6LIHna_FO= UNqMq6sJ_nc0OXQLdtHhXqhkptLrti1E36fdzEIjByybvPg$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8c-A0rdsMNZHVCH_SQet2G_MU0xkzZQqC_u6LIHna_FO= UNqMq6sJ_nc0OXQLdtHhXqhkptLrti1E36fdzEIjwGJxl7c$=20

=3D =3D =3D
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FOUS30 KWBC 100924
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
424 AM EST Sun Nov 10 2024

Day 1
Valid 12Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS CENTRAL AND
SOUTHWEST LOUISIANA...

Southwest and Central Louisiana...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northwest to north across portions of the
Central Gulf Coast through the Tennessee Valley. A slowly
advancing convective complex early this morning across southwest LA
is drifting eastward, showing hourly rain totals to 3" and
isolated totals to 13" thus far over portions of Allen Parish.
There is concern that this complex could hold together past 12z,
which is part of the reason for the upgrade to a Slight Risk, after coordinating with the LCH/Lake Charles LA forecast office.
Additional activity could form behind it closer to a surface
boundary in TX (could be forming at the present time) which is
expected to advect eastward during daytime heating. Moderate Risk
level impacts cannot be ruled out should such thunderstorm activity
persist over recently saturated soils into this afternoon.


Southeast Louisiana...
The guidance broadly remains unclear as to whether heavy rainfall
gets too far ashore southeast LA while mesoscale guidance shows the
complex to the west fizzling as it moves into the region.
Precipitable water values of 1.5-2" Sunday morning across southeast
LA advect offshore with time, which should limit heavy rainfall
concerns. Still, hourly rain totals to 2" and local totals to 4"
are possible on an isolated basis should storms backbuild or train.



Interior Southeast/Mid-South/Tennessee Valley...
The forward progress of the front should keep any excessive
rainfall concerns minimal in areas a bit north of the Gulf Coast
-- some of the risk area from eastern AR to the east-northeast just
south of the OH river accounts for recent rains/some soil
saturation. In this more northern portion of the Marginal Risk
area, hourly totals up to ~1" with local totals to 2" appear to be
the maximum potential. A decent amount of the area within the
Marginal Risk would find the forecasted rainfall welcome.

Changes to continuity were to shave off some of the northeast
portion of the Marginal Risk area, using 00z HREF probabilities of
0.5"+ as a guide, and include some of far southeast Texas to
account for the limited QPF signal there as soils are a bit more
sensitive after the past 24-36 hours of heavy rainfall.=20

Roth


Day 2
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Roth


Day 3
Valid 12Z Tue Nov 12 2024 - 12Z Wed Nov 13 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN AND NEAR
WESTERN WASHINGTON...

Precipitable water values of 0.75-1" advect in as a cold front
approaches, perhaps moves ashore, the Washington and northern
Oregon coast Wednesday morning. Inflow from the Pacific rises to
60 kts at 850 hPa out of the south-southwest with limited
instability available near and behind the front. The ingredients
appear to be there for hourly rain totals of 0.5"+, which would be
most problematic in burn scars. Over the full day, local amounts
of 3-4" are advertised for much of the guidance, which would be
most problematic along the Skokomish river in the Olympic
Peninsula. Enough was there in the guidance for the inherited
Marginal Risk area to remain from continuity; simplified its shape.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5kvhLCkZY1IM2rNEvrY0rpvZNem0Jw81UTcCw7OkUGyM= kBNwPTKKiwad5yPzScWTJYIUWJVsnEFDMMzBA9DwhV7cQnw$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5kvhLCkZY1IM2rNEvrY0rpvZNem0Jw81UTcCw7OkUGyM= kBNwPTKKiwad5yPzScWTJYIUWJVsnEFDMMzBA9DwSTYkCMI$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5kvhLCkZY1IM2rNEvrY0rpvZNem0Jw81UTcCw7OkUGyM= kBNwPTKKiwad5yPzScWTJYIUWJVsnEFDMMzBA9DwKOSLKMs$=20

=3D =3D =3D
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FOUS30 KWBC 101520
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1020 AM EST Sun Nov 10 2024

Day 1
Valid 16Z Sun Nov 10 2024 - 12Z Mon Nov 11 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS WESTERN AND
NORTHERN KENTUCKY AND SURROUNDINGS, AS WELL AS CENTRAL LOUISIANA...

...16z Update...

A Slight Risk has been added for western/northern KY and
surroundings, where 2-3" of rainfall over the past 3-6 hours has
led to a reduction in FFGs to 1.0" or less locally (and to 1.5-2.5"
for a broader surrounding area. With additional localized totals=20
of 2-3" anticipated over this saturated terrain, scattered
instances of flash flooding are possible (see MPD #1150 for more=20 information). The Marginal Risk area was also expanded considerably
north and east of what was inherited, due to isentropic upglide
having the potential to result in localized totals of 2"+ (per
40-km neighborhood probabilities for 2" exceedance as high as 10%)
with corresponding short-term FFGs of 1.5-2.0".=20

Elsewhere, only minor adjustments were necessary. The Slight Risk
for central LA and surroundings was reduced in size, confined to
where FFGs have been depressed to 2.0" or less due to the recent
extreme rainfall totals (as additional localized totals should
remain below that threshold).=20

Churchill


...Previous Discussion...

Southwest and Central Louisiana...
Moisture and instability from the Gulf gets advected from the
vicinity of Raphael northwest to north across portions of the
Central Gulf Coast through the Tennessee Valley. A slowly
advancing convective complex early this morning across southwest LA
is drifting eastward, showing hourly rain totals to 3" and
isolated totals to 13" thus far over portions of Allen Parish.
There is concern that this complex could hold together past 12z,
which is part of the reason for the upgrade to a Slight Risk, after coordinating with the LCH/Lake Charles LA forecast office.
Additional activity could form behind it closer to a surface
boundary in TX (could be forming at the present time) which is
expected to advect eastward during daytime heating. Moderate Risk
level impacts cannot be ruled out should such thunderstorm activity
persist over recently saturated soils into this afternoon.


Southeast Louisiana...
The guidance broadly remains unclear as to whether heavy rainfall
gets too far ashore southeast LA while mesoscale guidance shows the
complex to the west fizzling as it moves into the region.
Precipitable water values of 1.5-2" Sunday morning across southeast
LA advect offshore with time, which should limit heavy rainfall
concerns. Still, hourly rain totals to 2" and local totals to 4"
are possible on an isolated basis should storms backbuild or train.



Interior Southeast/Mid-South/Tennessee Valley...
The forward progress of the front should keep any excessive
rainfall concerns minimal in areas a bit north of the Gulf Coast
-- some of the risk area from eastern AR to the east-northeast just
south of the OH river accounts for recent rains/some soil
saturation. In this more northern portion of the Marginal Risk
area, hourly totals up to ~1" with local totals to 2" appear to be
the maximum potential. A decent amount of the area within the
Marginal Risk would find the forecasted rainfall welcome.

Changes to continuity were to shave off some of the northeast
portion of the Marginal Risk area, using 00z HREF probabilities of
0.5"+ as a guide, and include some of far southeast Texas to
account for the limited QPF signal there as soils are a bit more
sensitive after the past 24-36 hours of heavy rainfall.

Roth


Day 2
Valid 12Z Mon Nov 11 2024 - 12Z Tue Nov 12 2024

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Roth


Day 3
Valid 12Z Tue Nov 12 2024 - 12Z Wed Nov 13 2024

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN AND NEAR
WESTERN WASHINGTON...

Precipitable water values of 0.75-1" advect in as a cold front
approaches, perhaps moves ashore, the Washington and northern
Oregon coast Wednesday morning. Inflow from the Pacific rises to
60 kts at 850 hPa out of the south-southwest with limited
instability available near and behind the front. The ingredients
appear to be there for hourly rain totals of 0.5"+, which would be
most problematic in burn scars. Over the full day, local amounts
of 3-4" are advertised for much of the guidance, which would be
most problematic along the Skokomish river in the Olympic
Peninsula. Enough was there in the guidance for the inherited
Marginal Risk area to remain from continuity; simplified its shape.

Roth


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!41h9fAIpRjKHpPQpoOFVeSQ_kKJAY8CKo90Lv_Uh1U_0= mplk2sLYHiRwJS7cFA3CKu5r6PLB-PfWwDSsYXApMP2INwI$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!41h9fAIpRjKHpPQpoOFVeSQ_kKJAY8CKo90Lv_Uh1U_0= mplk2sLYHiRwJS7cFA3CKu5r6PLB-PfWwDSsYXAp7MgQj_Y$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!41h9fAIpRjKHpPQpoOFVeSQ_kKJAY8CKo90Lv_Uh1U_0= mplk2sLYHiRwJS7cFA3CKu5r6PLB-PfWwDSsYXApezhWDU4$=20

=3D =3D =3D
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