ACUS48 KWNS 060856
SWOD48
SPC AC 060855

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CDT Tue May 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
Late this week, an elongated upper trough from the Southeast into
the Northeast will evolve into a cutoff low centered roughly on the
Gulf Coast with stronger cyclonic flow remaining in the Northeast.
An upper-level ridge will continue to build in the West and Plains
and shift eastward into early next week. With the weak upper low
near the Gulf, this will spur repeated days of convection across
part of the Southeast and Florida. It is possible low-end severe
potential will exist with some of this activity until low/mid-level
lapse rates become poor. However, substantive severe threats are not
expected.

With the ridge building over the cutoff low, it will be slow to move
eastward. Model guidance suggests that this feature will reach the
East Coast around the middle of next week. At the same time, a
strong upper trough is expected to move into the West. Moisture
return into the Plains will begin as the trough moves eastward. That
said, at least a few days worth of offshore flow in the western Gulf
will likely limit the initial quality of that moisture return. The
potential for severe weather with the incoming western trough
remains uncertain at this point in time.

..Wendt.. 05/06/2025

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ACUS48 KWNS 070814
SWOD48
SPC AC 070813

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0313 AM CDT Wed May 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
From this weekend through early next week, an upper-level low will
be situated in the lower Mississippi Valley into the northern Gulf.
This feature will drive repeated days of convection within parts of
the Southeast into the Florida Peninsula. Lower-end severe potential
may occur with this activity, but how organized/intense it will be
is not certain. The upper-level low will become more progressive and
lift northeastward by the middle of next week. Shortwave ridging
aloft will move through the Plains into the Southeast in advance of
a western trough. With the presence of the upper low over the Gulf
Coast region, there will be offshore flow in the western Gulf for a
few days before moisture returns northward again in response to the
mid-week trough.

The largest uncertainty with this system will be the moisture
quality. Secondly, models currently project the strongest forcing to
be within the central/northern Plains, farther away from the
moisture plume moving north. At least as currently forecast, strong southwesterly/westerly winds aloft should overspread the
southern/central Plains by late next week. This particular trend in
guidance is recent and confidence is accordingly low, but model
trends will continue to be monitored in the coming days.

..Wendt.. 05/07/2025

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ACUS48 KWNS 080858
SWOD48
SPC AC 080856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Thu May 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
...Southeast into Mid-Atlantic...
By early next week, the cutoff upper low is forecast to become more
progressive and move northeastward. As this occurs, convection will
begin to overspread more of the Southeast into southern portions of
Florida and eventually the Mid-Atlantic. At this time, the potential
for several days of precipitation/cloud cover to impact surface
heating does not suggest a substantive severe threat will exist.
Furthermore, mid-level flow will weaken with time as the low lifts
northeast. Moderate mid-level winds will remain over Florida until
midweek. While Central/South Florida could see relatively higher
severe potential on Tuesday into Wednesday, models still show
limited destabilization on account of the uncertain surface heating
described earlier.

...Northern Rockies/Plains...
Strong upper-level winds will overspread the northern Rockies on
Sunday. Mid-level ascent should be sufficient for potentially
scattered storm development. Moisture still appears it may be
limited, but some threat for severe wind gusts may accompany storms
on Sunday in parts of southwest into central Montana. Uncertainty in
storm intensity precludes highlights, however. As the trough
continues to shift eastward, moisture return may be sufficient
enough to support some potential for severe storms mid to late next
week in parts of the Dakotas into Iowa/Minnesota. Aside from
questions about low-level moisture, timing and structure of the
trough varies in guidance and makes the coverage/intensity of storms
too uncertain for highlights.

...Central/southern Plains...
Model guidance continues to show the potential for a trough to
impact these regions by mid/late next week. Timing and position of
the stronger winds/greatest forcing continues to shift spatially,
however. Given that both the GEFS/EPS ensembles show a trough in the
mean next week does give some confidence in the general pattern.
Available ML guidance has also picked up on the pattern shift and
started to show an increased signal for severe potential. However,
significant uncertainties remain. With the cutoff nature of the
upper low in the lower Mississippi Valley, it is a feature that is
not predictable in terms of how fast it will depart. If guidance is
correct, it will move out right as the trough nears the Plains. This
leaves little time for a deep moist layer to develop and move
northward after a few days of offshore winds in the western Gulf.
Low-level moisture forecasts ahead of the trough do show mid/upper
60s F dewpoints. That said, the moisture profile in the vertical is
quite poor. It is not until next weekend that a signal for deeper
moisture is evident in model guidance. Lastly, shortwave ridging
will be in place ahead of the trough. Temperatures aloft do not
appear likely to appreciably cool given the current forecast
evolution of the trough and capping will be a concern. Trends in
guidance will continue to be monitored.

..Wendt.. 05/08/2025

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ACUS48 KWNS 090901
SWOD48
SPC AC 090859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Fri May 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
Based on the latest medium-range guidance, it appears that
large-scale mid/upper troughing will continue digging inland of the
Pacific coast, before gradually turning eastward toward the Rockies
during the early portion of next week. While this probably will be
accompanied by the development of modestly deep surface troughing
across the Great Plains, appreciable low-level moisture return, in
the wake of a mid-level low/trough slowly accelerating northeast of
the lower Mississippi Valley, through parts of the Mid South and
Ohio Valley, remains uncertain.

Even into mid-week, when it appears that the troughing may begin to
emerge from the Intermountain West/Rockies, while the downstream
troughing only slowly progresses across the Mid Atlantic, moisture
return (and destabilization) to the vicinity of the stronger forcing
for ascent may remain a potential limiting factor to severe
thunderstorm development.

Toward next Thursday/Friday, there does appear consensus that
stronger destabilization may begin to become better coupled with
large-scale forcing for ascent across the upper Mississippi
Valley/Midwest into Ohio Valley, as the mid-level troughing
progresses northeastward and eastward, around the periphery of
mid/upper ridging building north-northeast of the lower Mississippi
Valley. This appears to include at least a conditional risk for
organized severe convection, including a few supercells. Although
lingering uncertainties preclude introducing 15 percent or greater
severe probabilities at this time, this may change in later outlooks
for this period.

..Kerr.. 05/09/2025

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ACUS48 KWNS 100902
SWOD48
SPC AC 100900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Sat May 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Medium-range guidance indicates that a generally amplified, split
mid/upper flow will persist across the mid-latitude Pacific through
North America next week. It appears that this will include at least
a couple of significant troughs digging inland of the U.S. Pacific
Coast. The first may already be in the process of developing
eastward across the Intermountain West early in this period
(Tuesday), before progressing across the Rockies, Great Plains and
Mississippi Valley during the middle through latter portion of next
week. This may be followed by another significant trough digging
inland of the Pacific coast by early next weekend.

The lead trough will be relatively close on the heels of the
remnants of an initially broad quasi-stationary/cut-off low, which
may only slowly progress east of the Mississippi Valley through
Atlantic Seaboard during the early to middle portion of next week.
Low-level moisture return, in the wake of this perturbation and
ahead of the mid-level trough emerging from the West, may continue
to be impacted across at least parts of the Great Plains into mid
week. Thereafter, there appears a general consensus that there will
be a better coupling of large-scale forcing for ascent, aided by
surface cyclogenesis, with a notable increase in low-level moisture
and destabilization across the lower Missouri Valley into the Upper
Midwest and lower Ohio Valley by late next Thursday into Thursday
night. In the presence of strong shear, it appears that this
environment could become supportive of supercells and/or one or two
organizing severe storm clusters.

Machine learning output and other guidance suggests that potential
for strong to severe thunderstorms could persist and potentially
become more widespread across the Ohio Valley into Mid Atlantic, and
southern Great Plains, next Friday and Saturday. However,
uncertainties remain too large at this time to introduce greater
than 15 percent severe probabilities.

..Kerr.. 05/10/2025

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ACUS48 KWNS 110902
SWOD48
SPC AC 110900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Sun May 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
Latest medium-range output remains generally similar to prior runs
concerning the pattern evolution Wednesday into Thursday. A
significant short wave trough emerging from the Intermountain West
is forecast to support modest cyclogenesis across the central and
northern Great Plains through the mid/upper Mississippi Valley
vicinity. It appears that this probably will be accompanied by
increasing potential for strong to severe thunderstorm development,
with severe probabilities maximizing across parts of the Midwest
late Thursday into Thursday night, as the stronger large-scale
forcing for ascent becomes better coupled with substantive
boundary-layer moistening and destabilization. Aided by steep lower/mid-tropospheric lapse rates associated with elevated
mixed-layer air, and moderate to strong low-level and deep-layer
shear, it appears that the environment will become conducive to the
evolution of an upscale growing and organizing convective system.
But initial convection may include supercells posing a risk for
large hail and a couple of tornadoes, before damaging wind gusts
become the predominate severe hazard.

Based on the subsequent pattern evolution, it appears that this
convection could persist into, or re-intensify, Friday across parts
of the mid/upper Ohio Valley, with additional upscale growing
convection evolving along a stalling trailing cold front near the
southern edge of the stronger westerlies. Into next weekend,
renewed cyclogenesis appears possible along the trailing flank of
the front across the south central Great Plains, where additional
strong to severe thunderstorm development may focus along a
developing warm front, and a developing dryline southward through
the plains, as the warm sector destabilizes with increasing Gulf
moisture return.

However, by late Thursday into Friday, and beyond, these
developments remain much more unclear, as spread among and within
the various medium-range models begins to increase. Substantive
differences begin to develop concerning the progressiveness of the
lead trough, and a trailing short wave trough emerging from the
mid-latitude Pacific. The uncertain impacts of potentially multiple
evolving large convective clusters on succeeding days adds to low predictability.

..Kerr.. 05/11/2025

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ACUS48 KWNS 120901
SWOD48
SPC AC 120859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Mon May 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
An active period of severe weather is anticipated through early next
week based on recent trends in long-range guidance. A transition to
a progressive upper-level regime is expected over the next seven
days as a series of upper waves traverse the CONUS with favorable
wavelengths for air mass/moisture recovery into central portions of
the CONUS. Although both the GFS and ECMWF (and their respective
ensemble families) show similar synoptic evolutions through the
extended period, predictability in any severe threat currently
appears greatest on D4/Thursday and D5/Friday.

...D4/Thursday...
The upper-level trough currently over the Pacific Northwest is
forecast to eject into the upper MS River Valley through the day
Thursday with an attendant surface low deepening across the upper MS
Valley. A Pacific front is forecast to push east into an expanding
warm sector that should span from the MS River into the upper Great
Lakes and OH River Valley. Strong mid-level flow orthogonal to the
front should generally promote discrete/semi-discrete convection by
late afternoon on the eastern fringe of a stout EML. The consistent
signal for QPF within the warm sector coincident with 50-60 knot
mid-level flow and the intensifying nature of the synoptic low
suggests that a widespread severe weather event is possible and may
expand further east than depicted in previous forecasts. Despite
these trends, regional discrepancies among guidance limit confidence
in where the more robust severe corridors will become established.
Notable factors limiting confidence are the potential for strong
capping across much of the OH Valley and a faster progression of the
surface low/front in recent GFS/GEFS solutions (which typically
exhibit a fast bias at this range).

...D5/Friday...
The Pacific front/outflow associated with D4/Thursday's convection
is expected to stall across the lower OH Valley/mid-MS Valley before
gradually returning north as an effective warm front on Friday.
Ensemble guidance shows a reasonably strong signal for dewpoints in
the mid/upper 60s (potentially into the low 70s) along and south of
this boundary by peak heating. A mid-level impulse propagating over
the region should maintain elongated hodographs and provide
sufficient lift for thunderstorm development along the boundary.
This synoptic regime suggests that one or more organized
clusters/linear segments may propagate along the boundary and into
parts of the mid-MS Valley, lower OH Valley, and potentially into
the TN Valley. Given the thermodynamic and kinematic environment
forecast by ensemble guidance, such a cluster/line will likely pose
a severe threat. A 15% risk area has been introduced where the QPF
signal associated with this regime has been most consistent over
recent model runs, but further forecast refinements are expected.

..Moore.. 05/12/2025

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ACUS48 KWNS 130859
SWOD48
SPC AC 130858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Tue May 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
An active period of severe weather is anticipated through early next
week as a pair of upper-level troughs traverse the U.S. and will be
favorably timed to allow moisture recovery into central/southern
portions of the CONUS. The upper trough currently over the Pacific
Northwest is forecast to migrate into the Great Lakes region by this
weekend. In the wake of this feature, a second long-wave trough will
begin to deepen across the West before migrating into the Plains by
early/mid next week with attendant chances for strong/severe
thunderstorms.

...D4/Friday...
A stalled boundary will likely be draped from the Ozarks into the OH
Valley at the beginning of the forecast period. A weak,
low-amplitude mid-level perturbation emanating out of the central
Plains will promote secondary surface low development across the
southern Plains that will maintain southerly low-level flow. As
such, some northward migration of the boundary as an effective warm
front appears probable. Thunderstorm development along the boundary
is anticipated by late afternoon, and 40-50 knot mid-level flow
oriented along the frontal zone should promote initially
discrete/semi-discrete cells with the potential for upscale growth
into one or more organized clusters. Some disagreement in exactly
where the corridor of highest severe threat will become established
persists and is associated with the coverage and intensity of
ongoing convection Friday morning. Recent GFS/GEFS runs hint that
more isolated convection early Friday will allow for more aggressive
northward advancement of the front, while ECMWF solutions hint at
slower northward progression of the boundary. The 15% risk area has
been expanded to best encompass the overlap between these two
dichotomous solutions.

...D6/Sunday to D8/Tuesday...
A deepening upper level trough over the western states will promote
several days of lee troughing/cyclogenesis across the southern to
central High Plains beginning this weekend. This will allow for more
seasonal moisture return into the Plains with most ensemble members
showing dewpoints climbing into the low to mid 60s by D6/Sunday
afternoon across TX, OK, and southern KS. Deterministic solutions
continue to vary regarding the exact timing and evolution of the
upper-level wave (and any embedded impulses), but the general
consensus is that severe thunderstorms will be possible as
upper-level disturbances overspread the Plains and promote eastward
mixing of the dryline into an increasingly buoyant warm sector.
Confidence on any particular day remains too limited for risk
probabilities, but the overall synoptic regime and convective QPF
signals in ensemble guidance suggest that the potential for multiple
rounds of severe thunderstorms is increasing for the
southern/central Plains beginning D6/Sunday through D8/Tuesday.

..Moore.. 05/13/2025

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ACUS48 KWNS 140855
SWOD48
SPC AC 140853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Wed May 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
An active period of severe weather remains likely through the
weekend and into early next week for portions of the central CONUS.
A weakening upper trough is forecast to migrate across the Northeast
late this weekend as a second upper wave begins to amplify over the
western states. This upper regime will favor surface pressure falls
across the High Plains that will promote south/southeasterly return
flow into the southern/central Plains through early next week.
Severe thunderstorm chances will increase as preceding upper
disturbances and the primary upper wave eject into the Plains over
the warm sector. While severe weather chances are anticipated most
days through the extended period, confidence in more focused, synoptically-driven corridors is currently greatest on D5/Sunday and
D6/Monday across the southern Plains.

...D5/Sunday to D6/Monday...
Increasing southwesterly flow aloft over the southern/central
Rockies will promote lee cyclogenesis across the central High Plains
beginning D4/Saturday through D7/Monday. This will foster moisture
return into northern TX, OK, and southern KS as a warm front lifts
north. Long-range ensemble guidance suggests dewpoints ranging from
the mid 60s to low 70s are likely by Sunday afternoon across the
southern High Plains to the east of a sharpening dryline. Recent
GFS/GEFS solutions have come into better alignment with ECMWF/EPS
runs that depict a leading impulse within the subtropical jet
overspreading the southern High Plains late Sunday afternoon.
Enhanced westerly low- to mid-level flow coupled with ascent
associated with the upper feature should promote eastward mixing of
the dryline with attendant chances for thunderstorm development
within a buoyant and strongly sheared environment.

The ejection of the primary trough axis on D6/Monday should result
in more widespread 50+ knot mid-level flow overspreading much of
OK/KS. The eastward migration of the surface low and trailing
dryline through the day should provide adequate forcing for ascent
for thunderstorm development within a buoyant and strongly sheared
environment, which should promote an organized, and potentially more widespread, severe threat.

More specific mesoscale details for both days remain unclear at this
range, but the general alignment of global deterministic/ensemble
guidance regarding the overall synoptic regime and convective
environment, combined with a consistent QPF signal on both days,
suggests predictability is high enough to introduce risk
probabilities.

...D4/Saturday...
A residual cold front associated with a weakening surface low over
the northern CONUS is expected to be draped from the southern
Appalachians southwestward into the mid-MS Valley/Ozark Plateau
region. Sufficient buoyancy and strong zonal flow aloft will likely
support organized convection along the frontal zone. While some
severe threat is anticipated, mid-level ridging and lingering
convection at the start of the day limit confidence/predictability
in where the better mesoscale corridors for severe convection will
become established.

...D7/Tuesday...
Some severe threat is expected to persist into Tuesday as a surface
low and attendant trough/dryline migrate east towards the Midwest.
Ensemble guidance hints at strong/severe thunderstorm potential
across parts of AR, MO, and the lower OH Valley, but spread among
deterministic solutions and the potential for lingering convection
from D6/Monday limits confidence at this range.

..Moore.. 05/14/2025

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ACUS48 KWNS 150859
SWOD48
SPC AC 150858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Thu May 15 2025

Valid 181200Z - 231200Z

...DISCUSSION...
Medium-range guidance indicates that the persistent, prominent
mid/upper ridging across the mid-latitude and subtropical eastern
Pacific will become suppressed late this coming weekend into early
next week, before breaking down through the remainder of this
period. As it does, amplified downstream troughing is forecast to
emerge from the Intermountain West. Sunday, this may commence
gradually, with one significant lead short wave perturbation
pivoting north-northeast of the southern Rockies, accompanied by
cyclogenesis across eastern Colorado, as an upstream perturbation
continues to dig toward the Four Corners region. It appears that
this trailing perturbation will then pivot across the southern
Rockies through the central/southern Great Plains by late Monday,
perhaps accompanied by renewed cyclogenesis across the Texas
Panhandle into central Great Plains.

Both days, the dryline and warm front may provide focus for
organized severe convective development, including supercells, in
the presence of strong deep-layer shear and thermodynamic profiles characterized by steep lapse rates and sizable CAPE. It appears
that a substantive risk for strong to severe thunderstorms will
persist into at least Tuesday, within a broadening warm sector as
the cyclone and associated mid-level troughing shift a bit more
rapidly eastward across the middle Mississippi Valley.

Convective potential becomes more unclear Wednesday into Thursday as
the cyclone likely weakens and synoptic developments become more
uncertain across the East.

..Kerr.. 05/15/2025

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ACUS48 KWNS 160901
SWOD48
SPC AC 160900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Fri May 16 2025

Valid 191200Z - 241200Z

...DISCUSSION...
...D4/Monday - Central/Southern Plains into the Midwest...
A very moist and unstable environment will be present east of a
dryline across Kansas and Oklahoma on Monday morning. A surface low
across Kansas/Nebraska will weaken through the day and reconcentrate
farther south as a negatively tilted mid-level shortwave trough
moves into the central/southern Plains. The evolution of the upper
pattern will have some impact on the location and severity of the
severe weather threat on Monday. Despite these uncertainties, height
falls across a sharp dryline with a strongly unstable and uncapped
warm sector and supercell wind profiles should support severe storms
along and east of I-35 in Oklahoma and into southeast Kansas. All
severe weather hazards will be possible from any supercells which
mature on Monday.

Storms will be possible farther north across eastern Kansas and
western Missouri, but storm intensity is less clear given weaker
instability and messier storm mode along the warm frontal zone. In
addition, some elevated hail will be possible north of the warm
front into southeast Nebraska and Iowa.

...D5/Tuesday...
Thunderstorms will likely be ongoing at the beginning of the period
across the Midwest and perhaps as far south as eastern Oklahoma and
western Arkansas. These storms and their associated cloud cover will
have significant impact on destabilization across a broad warm
sector on Tuesday. A deepening mid-level low will develop across the
Plains and start to advance east on Tuesday. A strong mid-level jet
streak along the southern periphery of this upper low will
overspread the warm sector providing ample shear for storm
organization. Storm intensity remains uncertain on Tuesday due to
antecedent precipitation/cloud cover and differences in model
guidance. However, a broad region of strong to severe storms appears
possible from East Texas to northern Missouri and central Illinois
on Tuesday.

...Day 6-8...
A few strong to severe storms are possible on Day 6/Wednesday across
the Carolinas before the cold front moves offshore. Storm
coverage/intensity remains unclear at this time given the prior 2
days of storms and uncertainties in the upper-level pattern from
global guidance. Therefore, no probabilities are warranted at this
time. Beyond Day 6, severe weather concerns lessen as quality
moisture is mostly shunted offshore across the CONUS as a cold front
surges into the Gulf/Atlantic.

..Bentley.. 05/16/2025

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ACUS48 KWNS 170841
SWOD48
SPC AC 170840

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0340 AM CDT Sat May 17 2025

Valid 201200Z - 251200Z

...DISCUSSION...
...Day 4/Tuesday...
As the primary mid-level trough shifts east on Tuesday, scattered
severe thunderstorms are likely across parts of the Mid-Mississippi
Valley into the Tennessee Valley. Upper 60s to low 70s dewpoints
will be present ahead of a cold front. Convection/cloud cover from
Day 3 convection across the Plains/Ozarks will impact
destabilization across Kentucky and into the Ohio Valley. However,
farther south, strong destabilization is likely as the boundary
layer heats beneath steepening mid-level lapse rates. 50 to 60 knots
of mid-level flow will overspread this unstable warm sector during
the afternoon Tuesday. As this occurs, an uncapped boundary layer
and synoptic scale ascent should combine for scattered severe storm development. Wherever moderate to strong instability develops, most
likely south of the TN/KY border, supercells are anticipated with a
primary threat for large hail. By later in the evening, storms may
congeal into a MCS with an increasing damaging wind threat.

...Day 5/Wednesday...
A cold front will advance across the Appalachians on Tuesday
night/Wednesday morning. Moderate instability is forecast ahead of
this cold front Wednesday morning/early afternoon. A few strong to
severe storms may develop along the front before it moves into the
Atlantic. However, the limited duration of this threat, and
potential for timing shifts as newer guidance arrives, precludes
severe weather probabilities at this time.

...Day6-8..
A relatively benign severe weather pattern is expected from
Thursday/Day 6 into next weekend as a cold front pushes into the
Gulf. A few storms are possible along the cold front as it moves
south along the Florida Peninsula on Thursday. Otherwise, more
robust moisture recovery will begin Thursday night. Overall,
moisture quality will be low initially, but eventually some threat
may develop across the Plains as low-level moisture advection
continues.

..Bentley.. 05/17/2025

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ACUS48 KWNS 180846
SWOD48
SPC AC 180845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CDT Sun May 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
A few strong to isolated severe storms are possible in the eastern
Carolinas on Wednesday as a mid-level trough shifts east across the
eastern CONUS. It is unclear whether there will be substantial time
for destabilization before the surface low/front moves into the
Atlantic Ocean. Therefore, no probabilities are necessary for
Wednesday/D4 at this time.

Once this front moves offshore, a more benign period of severe
storms appears likely. The cold front will move south near the Gulf
Coast and into Florida with mostly sub 60s dewpoints across the
Eastern CONUS in its wake. Farther west the front is expected to
stall across Texas with low-level flow expected to advect moisture
westward to the High Plains on Thursday/D5.

Sufficient moisture should be in place by D7/Saturday across the
Plains. Therefore, some greater severe weather potential will likely
return by next weekend. However, uncertainty currently remains high
regarding the amplitude of the mid-level ridging and the location of
surface boundaries. Therefore, no probabilities have been introduced
at this time.

..Bentley.. 05/18/2025

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ACUS48 KWNS 190853
SWOD48
SPC AC 190852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CDT Mon May 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
A dry airmass will be in place across most of the eastern CONUS on
Thursday/D4 as a cold front moves into the western Atlantic and
stalls near the Gulf Coast. This will likely represent the minimum
threat during the extended severe weather period, with isolated
strong to severe storms across Texas likely the only threat area.

Starting Friday/D5, richer low-level moisture will advect over the
southern High Plains. However, this will also correspond to
shortwave ridging building across the Plains over the weekend
followed by zonal flow into early next week. This pattern may
support some localized threat each day, but more widespread,
predictable severe weather is unlikely at an extended range. As
these days draw closer, more confined regions of threat may become
more clear and allow for severe weather probabilities to be added.

..Bentley.. 05/19/2025

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