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  • DAY2SVR: Nws Storm Prediction Center Norman Ok

    From COD Weather Processor @1:2320/107 to All on Thu Aug 13 06:20:54 2026
    ACUS02 KWNS 130601
    SWODY2
    SPC AC 130559

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1259 AM CDT Thu Aug 13 2026

    Valid 141200Z - 151200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
    HIGH PLAINS EASTWARD INTO PARTS OF THE MIDWEST...OHIO VALLEY...AND MID-ATLANTIC...

    ...SUMMARY...
    Isolated strong to severe storms are possible from the central High
    Plains into parts of the Midwest, Ohio Valley, and Mid-Atlantic on
    Friday.

    ...Synopsis...
    An upper ridge initially covering parts of the lower MS Valley and
    Southeast is forecast to build northward on Friday. Despite the
    building ridge, multiple MCVs may traverse the periphery of the
    ridge, helping to focus strong to locally severe storm development
    within a moist and unstable environment extending from the central
    Plains into the Midwest, Ohio Valley, and Mid-Atlantic/Carolinas.

    ...Ohio Valley into parts of the Mid-Atlantic...
    Elevated convection and possibly a remnant MCS may be ongoing Friday
    morning across parts of the Ohio Valley. Guidance varies regarding
    the organization/intensity of this morning convection, and whether
    it is associated with a well-defined MCV. In general, an isolated
    wind-damage threat could accompany the morning convection before it
    weakens, with some rejuvenation of wind-damage potential possible
    into parts of the Mid-Atlantic and NC, in conjunction with diurnal heating/destabilization. Some clustering and locally greater
    wind-damage potential may evolve across some part of the region, but uncertainty remains rather high regarding the details.

    The 12/00Z NAM is an aggressive outlier, depicting a strong MCV
    approaching the Mid-Atlantic region during the afternoon, and
    substantial destabilization farther north across the Mid-Atlantic
    compared to other guidance. While confidence in this particular
    scenario is low, some expansion was made to the Marginal Risk across
    the Mid-Atlantic and NC, to account for uncertainty regarding the
    most favored corridor.

    ...East-central Plains into the Midwest...
    Elevated convection will also likely be ongoing Friday morning from
    eastern NE into parts of IA/IL and vicinity. An isolated severe
    threat cannot be ruled out with this convection, though early-day
    storms may tend to diminish in conjunction with a weakening
    warm-advection regime.

    In the wake of morning convection, moderate to strong buoyancy is
    expected to develop near/north of the outflow-influenced frontal
    zone during the afternoon, aided by rich low-level moisture. Veering
    low-level wind profiles near/north of the front will result in
    favorable effective SRH, though mid/upper-level flow will be modest
    at best and may weaken somewhat with height.

    Most guidance suggests an MCV may emerge from the central High
    Plains and move along the periphery of the ridge through the
    afternoon/evening, though the timing and trajectory of such a
    feature remains uncertain. Any MCV-related uptick in storm coverage
    would result in a greater potential for organized severe storms.
    Otherwise, isolated strong to severe storms will still be possible.
    The favorable effective SRH could support initial supercell
    development, with some potential for all severe hazards. The weak to
    modest mid/upper-level flow could result in a quick transition to
    more of a cluster mode, potentially increasing wind-damage
    potential.

    ...CO Front Range into the central High Plains...
    Low-level east/southeasterly flow will again promote moderate
    destabilization and scattered storm development in the vicinity of
    the CO Front Range Friday afternoon. Deep-layer flow/shear will
    generally be weak to modest, but the strongest cells may become
    capable of producing isolated hail and localized severe gusts.
    Farther south/east, high-based convection may develop into parts of
    the south-central High Plains, within a hot and well-mixed
    environment. Localized severe gusts could accompany these high-based
    storms.

    Friday evening into the overnight, expanding outflow and an
    increasing low-level jet may allow for one or more upscale-growing
    clusters to develop and move across western KS (and perhaps
    southwest NE). The intensity and longevity of any such clusters
    could be limited by weak mid/upper-level flow, but some threat for
    strong to severe gusts could persist into early Saturday morning.

    ..Dean.. 08/13/2026

    $$

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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Thu Aug 13 17:32:18 2026
    ACUS02 KWNS 131732
    SWODY2
    SPC AC 131730

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1230 PM CDT Thu Aug 13 2026

    Valid 141200Z - 151200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
    HIGH PLAINS EASTWARD INTO PARTS OF THE MIDWEST...OHIO VALLEY...AND MID-ATLANTIC...

    ...SUMMARY...
    Isolated strong to severe storms are possible from the central High
    Plains into parts of the Midwest, Ohio Valley, and Mid-Atlantic on
    Friday.

    ...East-central Plains into the Midwest...
    Isolated severe potential will be possible with early morning
    elevated storms within a warm advection regime. These storms will
    generally diminish with time given the weakening low-level jet. An
    MCV will likely emanate from the central High Plains and impact the Mid-Missouri Valley during the afternoon. This MCV will track along
    the periphery of the upper ridge that will be building into the
    Plains/Midwest. Model guidance varies with regard to how organized
    this MCV and associated surface reflection will be. Moderate to
    strong instability is expected to develop near the effective surface
    boundary by the afternoon despite some expected cloud cover. The
    timing of convective development is quite uncertain. The HRRR
    suggests strong enough convergence at the surface that storms will
    form by late afternoon. Many other CAMs suggests development after
    00Z as the low-level jet increases again. Storms that do develop
    will likely have supercell characteristics initially, but weak flow
    above 500 mb will tend to lead to outflow dominance and clustering.
    Should confidence in late afternoon development increase, there may
    be greater severe potential than currently expected.

    ...Ohio Valley into parts of the Mid-Atlantic...
    Convection will likely be ongoing across portions of the Ohio Valley
    into the central Appalachians early Friday morning. Model guidance
    generally suggests that an MCV feature will be associated with this
    activity, though the strength of the MCV varies. Regardless of how
    strong the MCV is, there is a consistent signal for cloud cover
    limiting destabilization/low-level lapse rates across much of these
    regions. Stronger mid-level winds will also be displaced from the
    larger buoyancy values in the Carolinas. Given the timing of the
    MCV, it appears likely that wind damage potential will be spatially
    limited. There will be a small corridor of stronger heating in
    southeast Virginia/northeast North Carolina which could see locally
    stronger storms.

    ...CO Front Range into the central High Plains...
    Moist east/southeasterly surface winds into the higher terrain will
    again promote scattered storm development within the Front Range.
    Deep-layer shear will not be overly strong, but a few storms will be
    capable of isolated hail and severe winds. Additional storms are
    expected in the hotter, well-mixed environment to the south and
    east. These storms will be capable of severe winds. There will be
    some increase in the low-level jet during the evening. The strongest
    850 mb winds will be focused farther east, however. If a cluster can
    form, it may persist farther eastward into later in the evening.

    ..Wendt.. 08/13/2026

    $$

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Fri Aug 14 05:53:52 2026
    ACUS02 KWNS 140553
    SWODY2
    SPC AC 140551

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1251 AM CDT Fri Aug 14 2026

    Valid 151200Z - 161200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
    HIGH PLAINS...AND FROM THE OHIO VALLEY INTO THE CAROLINAS...

    ...SUMMARY...
    Strong to severe storms are possible on Saturday from the central
    High Plains eastward into parts of the Midwest, Ohio Valley,
    southern/central Appalachians, and Carolinas.

    ...Ohio Valley...

    An MCV is forecast to be located in the vicinity of eastern
    IA/northern IL Saturday morning. A surface boundary will be draped
    northwest to southeast across lower MI toward WV while the surface
    low/MCV shifts east across southern Lake MI toward the Lower Great
    Lakes through the evening. A very moist airmass will be in place,
    and at least a narrow corridor of strong instability may develop.
    Spread among forecast guidance remains fairly large regarding these
    surface features and corridors of greater destabilization.
    Nevertheless, stronger vertical shear in the vicinity of the surface
    low/MCV will support organized severe convection. Damaging winds and
    perhaps a tornado or two will be possible as convection develops
    near the MCV and southeastward along the surface boundary toward
    WV/eastern KY.

    ...VA/Carolinas into the Southeast...

    Scattered thunderstorms are expected to develop over higher terrain
    within a very moist and moderately unstable airmass Saturday
    afternoon. Vertical shear will remain modest, especially with
    southward extent into GA/FL, but strong heating could support
    sporadic downbursts within the high-PW environment. If sufficient
    clustering occurs over higher terrain, a forward-propagating cluster
    could move across portions of the Carolinas, producing greater risk
    for damaging gusts.

    ...Central High Plains to the MO Valley...

    Another MCV is forecast to be located over KS/NE, moving toward the
    Mid-MO Valley. Downstream destabilization is uncertain as this
    airmass will have been modified by the downstream MCV moving into
    the Midwest. Meanwhile, a moist airmass will be in place westward
    into the central High Plains. Upslope flow will support scattered
    thunderstorm development over higher terrain by early/mid afternoon.
    As convection spreads eastward into eastern CO and vicinity, steep
    lapse rates and modest but favorable shear profiles will support at
    least transient organized cells capable of producing large hail and
    damaging gusts. Additional convection may develop eastward across NE
    ahead of a surface cold front, mainly posing a risk for isolated
    damaging gusts.

    ..Leitman.. 08/14/2026

    $$

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Fri Aug 14 17:27:24 2026
    ACUS02 KWNS 141727
    SWODY2
    SPC AC 141725

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1225 PM CDT Fri Aug 14 2026

    Valid 151200Z - 161200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
    HIGH PLAINS...AND FROM THE OHIO VALLEY INTO THE CAROLINAS...

    ...SUMMARY...
    Strong to severe storms are possible on Saturday from the central
    High Plains eastward into parts of the Midwest, Ohio Valley,
    southern/central Appalachians, and Carolinas.

    ...Synopsis...
    The upper ridge is expected to broaden and expand westward on
    Saturday. Modest to regionally moderate flow aloft will be confined
    to the northern half of the CONUS. A convectively modified surface
    boundary from the Mid-Atlantic westward into the Midwest and central
    Plains will be the general focus for convection outside of MCV
    features moving around the upper ridge.

    ...Midwest/Ohio Valley...
    An MCV is forecast to be in northern Illinois/southern Wisconsin
    Saturday morning. This feature will track eastward during the day.
    Scattered storms are expected near the MCV and along a surface
    boundary from the southern Great Lakes region into the central
    Appalachians. Early morning precipitation and cloud cover associated
    with the MCV is may limit surface heating, but the very moist
    airmass will not need much heating to destabilize. Damaging winds
    will be the main threat with a tornado or two possible, particularly
    near the MCV. Storms may only be organized for short periods given
    weak lapse rates and shear concentrated in the lower half of the
    troposphere.

    ...Central High Plains into the Missouri Valley...
    Another MCV is expected to track eastward through the central Plains
    into Iowa/Missouri. Given the impacts of the preceding MCV on
    Friday, it is not clear how much destabilization, and therefore
    storm coverage will occur. Should afternoon storms develop, the
    strongest activity will likely be on the southern flank of the MCV
    from northeast Kansas into northern Missouri. Later in the evening,
    additional storms are possible along the cold front.

    Farther west, flow aloft in the central Rockies will become more
    westerly. At the surface, continued moist upslope flow will promote
    scattered to numerous storms by afternoon. Cloud cover may keep
    temperatures somewhat cool, but steep lapse rates aloft and around
    35-40 kt of effective shear near the terrain will support transient
    supercell structures capable of large hail and severe wind gusts.
    Storm/outflow interaction is likely with a few clusters propagating
    eastward with time.

    ...Southern Appalachians into the Piedmont...
    Strong heating of at least low 70s F dewpoints will promote strong
    instability by the afternoon. Flow aloft will be weak to modest from
    the northwest. Though storms may not be very organized, scattered
    convection within the terrain may move east/southeast with time. One
    or more clusters may develop leading to localized corridors of wind
    damage potential.

    ...Central/Northern Minnesota...
    A cold front will be the focus for potential isolated storm
    development. Mid-level forcing for ascent will be quite weak and
    thermodynamic profiles will be marginal. Should storms develop,
    isolated strong outflow winds would be possible. Severe potential
    remains too limited for probabilities.

    ...Northeast Oregon into central Idaho...
    With a subtle shortwave trough moving through during the afternoon, thunderstorms are likely to develop within the Blue Mountains and
    move northeastward. Modest buoyancy and effective shear will promote
    a couple of stronger storms. Small hail and gusty outflow winds may
    occur, but severe potential appears limited.

    ..Wendt.. 08/14/2026

    $$

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sat Aug 15 05:12:26 2026
    ACUS02 KWNS 150512
    SWODY2
    SPC AC 150510

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1210 AM CDT Sat Aug 15 2026

    Valid 161200Z - 171200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE OHIO VALLEY TO THE SOUTHERN MID-ATLANTIC...AND ACROSS THE
    CENTRAL HIGH PLAINS...

    ...SUMMARY...
    Severe storms are possible across parts of the Ohio Valley to the
    Mid-Atlantic, and in parts of the central High Plains Sunday
    afternoon and evening.

    ...Midwest to Mid-Atlantic...

    A couple of shortwave impulses/MCVs are expected to move across the
    region on Sunday within broad, modestly enhanced deep-layer
    west/northwesterly flow. One of these shortwave impulses may be
    located over the Upper Ohio Valley Sunday morning, resulting in
    ongoing cloudiness and possible convection across parts of PA/NJ and
    the DelMarVa vicinity. This poses some uncertainty for severe
    potential during the afternoon with northward extent across the
    Mid-Atlantic. However, further south, stronger heating is
    anticipated along with modest destabilization. A second shortwave
    impulse/MCV will overspread the area by afternoon, supporting
    additional thunderstorm develop over the upper Ohio Valley toward
    the Blue Ridge. Sufficient clustering may occur as convection
    organizes and spreads southeast through early evening, posing a risk
    for damaging gusts.

    Further north and west across the Lower Ohio Valley into the Mid-MS
    Valley, a very moist and strongly unstable airmass will be in place
    ahead of southeastward-advancing cold front. Vertical shear will
    generally be weak, but scattered storms developing along the front
    will be moving into a very unstable airmass with PW values
    near/greater than 2 inches. This could support isolated to widely
    scattered storms capable of wind damage.

    ...High Plains...

    Easterly low-level flow will maintain a modestly moist boundary
    layer on Sunday. Strong heating and steep midlevel lapse rates will
    aid in moderate destabilization. Effective shear magnitudes around
    30-40 kt will support organized cells moving east/southeast off
    higher terrain by late afternoon through early evening. Large hail
    and isolated strong wind gusts will be possible.

    ..Leitman.. 08/15/2026

    $$

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sat Aug 15 17:31:30 2026
    ACUS02 KWNS 151731
    SWODY2
    SPC AC 151729

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1229 PM CDT Sat Aug 15 2026

    Valid 161200Z - 171200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
    OHIO VALLEY TO MID ATLANTIC...AND OVER THE CENTRAL HIGH PLAINS...

    ...SUMMARY...
    Severe storms are possible across parts of the Ohio Valley to the
    Mid-Atlantic, and in parts of the central High Plains Sunday
    afternoon and evening.

    ...OH Valley eastward into VA...
    A weak shortwave trough associated with ongoing convection is
    forecast to move across the OH Valley and into VA late. Low pressure
    is forecast to develop near the Lower Great Lakes, with a trough
    sweeping across OH, western PA and WV. In the wake of early
    activity, strong heating near the surface trough along with 70s F
    dewpoints will yield moderate instability, with scattered storms
    developing during the afternoon and spreading rapidly
    east/southeast.

    Shear profiles appear sufficient for a few supercells, but midlevel
    lapse rates will be poor which will limit hail potential. Veering
    winds with height and effective SRH over 200 m2/s2 may support a
    brief tornado, but damaging wind gusts appear most likely as the air
    mass will be very moist and 850 mb winds increase out of the
    southwest at over 30 kt resulting in progressive outflows.

    ...High Plains...
    Midlevel northwest winds will range from 15 kt over northeast NM to
    25-30 kt from CO northward, while surface winds remain weak and out
    of the southeast. This will maintain the moist air mass over the
    region as strong heating leads to 1000-1500 J/kg MLCAPE from NM
    northward to the Black Hills. Scattered afternoon storms are likely
    to initiate in the uncapped air mass near the higher elevations,
    with perhaps a greater storm concentration over CO and NM.
    Sufficient deep-shear will favor cells capable of hail over 1.00".
    Some clusters is likely especially over southern areas, with
    additional strong gusts possible into the TX/OK Panhandles where a
    weak wind shift will exist.

    ..Jewell.. 08/15/2026

    $$

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sun Aug 16 05:28:38 2026
    ACUS02 KWNS 160528
    SWODY2
    SPC AC 160526

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1226 AM CDT Sun Aug 16 2026

    Valid 171200Z - 181200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
    NEBRASKA AND THE MID-MISSOURI VALLEY...AND ACROSS THE SOUTH-CENTRAL APPALACHIANS...

    ...SUMMARY...
    Strong to severe thunderstorms are possible Monday afternoon and
    evening across portions of the northern and central Plains, and
    parts of the southern Appalachians/Carolinas.

    ...Northern/Central Plains...

    An upper shortwave trough will deepen as it develop east/southeast
    across Ontario and the Upper Midwest, resulting in broader height
    falls from the northern/central Plains to Great Lakes. As this
    occurs, 40-50 kt northwesterly flow aloft will overspread the
    region. At the surface, a cold front will extend from northwest MN
    into western NE by 00z. Ahead of the front, a corridor of 60s F
    dewpoints are expected across central/eastern NE into IA/southeast
    SD and MN. Isolated to scattered thunderstorms are likely to develop
    by late afternoon ahead of the surface boundary. Modestly steep
    lapse rates and strong heating of the moist boundary layer will
    result in 2500-3500 J/kg MLCAPE amid 35+ kt effective shear
    magnitudes. This should result in organized supercells structures
    capable of large hail and damaging gusts. There is some potential
    upscale growth could occur during the evening across NE as a modest
    low-level jet develops. If this occurs, the damaging wind risk could
    increase.

    ...South-central Appalachians...

    A vorticity max located over the Lower OH Valley will develop
    east/southeast through 30-40 kt west/northwesterly flow aloft Monday
    afternoon and evening. A very moist and unstable airmass will be in
    place amid strong daytime heating. Large-scale ascent will increase
    as the vorticity maxima approaches during the afternoon, and a
    surface boundary begins to sag south/southeast over the region.
    Steep low-level lapse rates, high PW values, and 25-30 kt effective
    shear magnitudes could result in organized clusters producing
    damaging gusts through evening.

    ..Leitman.. 08/16/2026

    $$

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Mon Aug 17 13:31:18 2026
    ACUS02 KWNS 161734
    SWODY2
    SPC AC 161732

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1232 PM CDT Sun Aug 16 2026

    Valid 171200Z - 181200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
    NORTHERN PLAINS...AND FROM THE SOUTHERN APPALACHIANS INTO THE
    CAROLINAS...

    ...SUMMARY...
    Strong to severe thunderstorms are possible Monday afternoon and
    evening across portions of the northern and central Plains, and
    parts of the southern Appalachians/Carolinas. Isolated severe gusts
    may occur over Oklahoma.

    ...Northern Plains...
    Stronger winds aloft will overspread the area on Monday with a front
    pushing across the region. While temperatures aloft will be cool,
    low-level moisture will not be excessive.

    Storms are expected to form by 20Z over eastern ND and west-central
    MN, and over the Black Hills. The steep lapse rate environment, with
    modest MUCAPE values of 1000-1500 J/kg along with elongated mid to
    upper level hodographs will favor cells producing hail over 1.00". A greater/more concentrated severe risk is expected near and after
    00Z, as activity matures as it moves southeastward into stronger
    instability from NE into southeast SD. Additional cells are also
    anticipated over central NE. Large hail is probable with all this
    activity, with scattered severe gusts as storms merge/cluster during
    the evening. A brief tornado cannot be ruled out late day/early
    evening as low-level shear increases with a southwesterly low-level
    jet.

    ...Southern Appalachians/Carolinas Vicinity...
    The ridge over the Southeast will weaken a bit as a midlevel waves
    moves through during the day. Speed at 500 mb will average near 30
    kt, with 15-20 kt at 850 mb. This will aid southeastward storm
    motions as development occurs within the surface trough/wind shift
    from NC and southern VA into TN. Precipitable water near 2.00"
    combined with the afternoon well-mixed boundary layer should support
    gusty outflow winds, with a few severe gusts over 50 kt possible.
    Activity should wane after about 03Z.

    ...Parts of OK into AR...
    Dewpoints are forecast to be relatively high near a weakening
    boundary/wind shift that will extend roughly from the TX Panhandle
    across central/southern OK and into central AR. Daytime heating will
    then lead to a narrow east-west oriented corridor of steep boundary
    layer lapse rates, and strong instability. Shear will be weak, and
    so will forcing for ascent. However, several CAMs indicate at least
    isolated cells developing during the late afternoon, and locally
    severe downbursts may occur.

    ..Jewell.. 08/16/2026

    $$

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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Mon Aug 17 14:01:02 2026
    ACUS02 KWNS 170542
    SWODY2
    SPC AC 170540

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1240 AM CDT Mon Aug 17 2026

    Valid 181200Z - 191200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS FAR
    SOUTHEAST SOUTH DAKOTA...PARTS OF NEBRASKA...NORTHERN KANSAS AND
    MISSOURI...AND IOWA...

    ...SUMMARY...
    Severe thunderstorms capable of large hail and damaging wind gusts
    are expected Tuesday afternoon/evening across parts of the central
    Plains and toward the Lower Missouri/Mid-Mississippi Valley.

    ...Central Plains to Mid/Upper MS Valley...

    The forecast for Tuesday has become less certain with time, with
    current CAMs guidance suggesting early convection across parts
    NE/IA/MO early in the period. This could have implication on
    boundary layer destabilization later in the afternoon/evening and
    how convection develops/evolves during that time.

    Nevertheless, an otherwise favorable environment for severe storms
    could develop as an upper trough continues to dig over the Great
    Lakes, leading to modest height falls across the northern/central
    Plains to the Midwest. Northwesterly flow aloft will increase to
    around 40-50 kt in the midlevels, providing support for supercell
    wind profiles across the region. Meanwhile, a moist boundary layer
    will be in place ahead of a southeastward-advancing front. Morning
    convection could result in a convective enhance surface boundary
    and/or outflow across portions of the NE/KS/MO/IA. Where stronger
    heating can occur within the very moist warm sector, resulting in
    stronger differential heating, convection is expected to develop by
    late afternoon into the evening. This could be storms along one or
    more boundaries across the broader region. Large hail and strong
    gusts will be possible with initial storms. A low-level jet is
    expected to strengthen during the nighttime hours, and some
    potential for MCS development is apparent, but conditional. Should
    this occur, potential for damaging wind gusts would increase.

    More isolated storms are expected across the High Plains from
    eastern WY/northeast CO into southwest SD/western NE/KS are
    expected, and into parts of MN/WI, posing a risk for strong gusts
    and/or hail.

    ...Southeast...

    A surface low is forecast to move across NC and lift northward along
    the East Coast. This will bring a surface front across the
    Southeast, where a very moist and moderately unstable airmass will
    be in place beneath deep-layer northwesterly flow. Vertical shear
    will remain weak, but multi-cell clusters could produce sporadic wet
    downbursts within the high PW environment. Overall, severe potential
    is expected to remain limited, precluding severe probabilities at
    this time.

    ..Leitman.. 08/17/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Mon Aug 17 17:28:44 2026
    ACUS02 KWNS 171728
    SWODY2
    SPC AC 171727

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1227 PM CDT Mon Aug 17 2026

    Valid 181200Z - 191200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTHERN KANSAS...CENTRAL TO SOUTHEAST NEBRASKA...SOUTHWEST IOWA...AND
    NORTHWEST MISSOURI...

    ...SUMMARY...
    Severe thunderstorms capable of large hail and damaging wind gusts
    are expected Tuesday afternoon/evening across parts of the central
    Plains and toward the Lower Missouri/Mid-Mississippi Valley.

    ...Central Plains to Mid/Upper MS Valley...
    The presence, or lack, of morning convection will have a significant
    impact on the evolution of storms on Tuesday. From the 12Z HREF
    cycle, a majority of the CAM members have a cluster of storms across
    eastern Nebraska at 12Z. Given the environment in the region, this
    cluster would at least have some marginal hail/wind threat. Most
    guidance has this cluster dissipating as the low-level jet weakens.
    Given a more stable environment east of this activity this seems
    like the most likely scenario. If this cluster can persist until
    late morning when the downstream airmass destabilizes to the south,
    it could turn right and persist across Missouri, but evidence for
    this is quite low.

    Whatever boundaries any morning storms leave behind will likely be
    the focus for diurnal storm development. Overall forcing is quite
    low which may lead to isolated to widely scattered storm
    development. However, 45 to 55 knots of mid-level flow from the
    KS/NE border northward will provide ample shear for storm
    organization, including supercells. In fact, some 2-3 inch hail
    seems likely with any longer-lived supercells which may develop
    within this most favorable environment.

    Additional thunderstorms are expected during the overnight period
    from northern Kansas to central Missouri, within a region of
    isentropic ascent. The location of the 850mb front and the best
    forcing still has some uncertainty, but thunderstorm activity will
    be most likely from northeast Kansas to northwest Missouri. As
    storms congeal and a cold pool forms, a wind-producing MCS may
    develop out of this cluster. This is most prominently shown by the
    WRF-NSSL and the WRF-ARW. Therefore, a CIG1 wind intensity has been
    added across this region for this conditional 75+ mph wind threat
    associated with a MCS in the forecast environment.

    ..Bentley.. 08/17/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Tue Aug 18 05:48:24 2026
    ACUS02 KWNS 180548
    SWODY2
    SPC AC 180546

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1246 AM CDT Tue Aug 18 2026

    Valid 191200Z - 201200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
    MISSOURI INTO NORTHERN ARKANSAS...AND INTO SOUTHERN ILLINOIS AND FAR
    WESTERN KENTUCKY AND TENNESSEE...

    ...SUMMARY...
    Isolated strong to severe thunderstorms may produce hail and strong
    to severe wind gusts from the central Plains to the Mid-Mississippi
    Valley and Ozarks. The greatest risk area is from the Ozarks into
    the Lower Ohio Valley Wednesday afternoon and evening.

    ...Southern MO...Northern AR...Western KY/TN...Southern IL...
    Gradual height falls will occur throughout the period as a
    low-amplitude shortwave trough moves out of the Plains and toward
    Mid MS/OH Valleys. Early day thunderstorms may be ongoing from MO
    into the Lower OH Valley, but perhaps not particularly strong.
    Behind this initial activity, strong instability will redevelop from
    MO into northern AR, and western KY/TN with southwest low-level
    winds and 70s F dewpoints near a southward moving front over
    southern MO. Predictability is a bit low for the boundary position,
    but storms may form anywhere from I-70 southward into northern AR
    during the late afternoon, moving east/southeast during the evening.
    Corridors of damaging wind and hail will be possible, with any brief
    tornado chances depending on earlier outflows which may enhance
    low-level shear.

    ...Central and Northern Plains...
    A shortwave trough will move from the northern Plains into the Mid
    MS Valley on Wednesday, with 40 kt northwest flow at 500 mb across
    much of the central Plains. Although a front will push south across
    OK and the TX Panhandle, low-level moisture with 50s to 60s F
    dewpoints will remain beneath this upper trough, and strong heating
    will lead to clusters of storms within a weak surface trough/wind
    shift by late afternoon. Favored areas will be from SD into NE where temperatures aloft will be cold and counteract the lack of low-level
    moisture, and from the Front Range southward into northeast NM.
    Scattered hail over 1.00" or locally severe gusts will be possible
    through early evening as storms travel southeastward out of the High
    Plains and across SD, NE and KS.

    ..Jewell.. 08/18/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Tue Aug 18 17:32:26 2026
    ACUS02 KWNS 181732
    SWODY2
    SPC AC 181730

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1230 PM CDT Tue Aug 18 2026

    Valid 191200Z - 201200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WEDNESDAY INTO
    WEDNESDAY NIGHT ACROSS MUCH OF SOUTHERN MISSOURI...PARTS OF SOUTHERN ILLINOIS...WESTERN KENTUCKY AND TENNESSEE AND NORTHERN ARKANSAS...

    ...SUMMARY...
    One or two organized clusters of thunderstorms with potential to
    produce swaths of damaging surface gusts appear possible across
    parts of the Ozark Plateau into Mid South, and perhaps central and
    southeastern Arizona, Wednesday through Wednesday night.

    ...Discussion...
    An initially notable cyclone to the southwest of Hudson Bay is
    forecast to weaken, with its broadening mid-level circulation
    redeveloping across and east of southern Hudson/James Bays through
    this period. To the south of this feature, broad cyclonic mid-level
    flow will overspread much of the Upper Midwest/Great Lakes and Ohio
    Valley through Northeast, downstream of initially building mid-level
    ridging across the Pacific Northwest through northern Rockies, to
    the north of a prominent mid-level high slowly shifting
    northeastward toward the Four Corners region.

    Beneath a plume of elevated mixed-layer now advecting along the
    southern fringe of the westerlies, across the central Great Plains,
    toward the Mid South, a lower-level baroclinic zone, likely
    reinforced by convective outflow, may be in the process of advancing
    southward across the Mid South/Ozark Plateau and south central Great
    Plains (Kansas/Oklahoma border vicinity) at the outset of the
    period. In the wake of one possible MCV initially migrating
    east-southeastward into the Mid South, and ahead of a possible
    trailing MCV, and trailing digging short wave impulse, it appears
    that the southward progression of the front may slow or stall across
    the Ozark Plateau/Mid South, while continuing more steadily, but
    slowly, across Oklahoma and the Texas Panhandle. There is
    substantive spread evident in the model output concerning these
    developments, however.

    ...Ozark Plateau/Mid South...
    Potential convective evolution Wednesday through Wednesday night
    remains uncertain. However, it appears that a notable belt of
    convectively augmented mid-level flow, including 30-50+ kt around
    700 mb, will gradually nose from the lower Missouri through lower
    Ohio Valley during the day. Depending on how the near-surface
    boundary becomes oriented as this occurs, aided by a corridor of
    seasonably high moisture content along it, there appears potential
    for destabilization and shear to become conducive to organized
    severe thunderstorm development. This may include supercells and/or
    one or two evolving clusters accompanied by developing swaths of
    strong to severe wind gusts through the period.

    ...Southern Rockies into Great Plains...
    In the wake of the primary front, it appears that the boundary-layer
    will remain sufficiently moist to support modest instability in the
    presence of relatively weak mid-level inhibition across the middle
    into lower Missouri Valley. Aided by forcing for ascent associated
    with one lead digging short wave impulse, and a trailing one digging into/across the international border, at least widely scattered
    strong to severe storm development appears possible through the
    period, in the presence of favorable strong deep-layer shear.

    A drier, but more strongly heated and deeply mixed boundary-layer by
    late Wednesday afternoon, near and to the lee of the Front Range
    through Sangre de Cristo Mountains, may also become conducive to
    widely scattered to scattered strong storms with potential to
    produce severe wind and hail, aided by a weak short wave impulse
    migrating around the Four Corners ridge.

    ...Arizona...
    With the evolution/progression of the mid-level ridge, potential
    steering flow for convective development is forecast to take on a
    prominent easterly component with weak to modest strength by late
    Wednesday afternoon across much of the Mogollon Rim through lower
    deserts. Coupled with a preceding Gulf moisture surge, forecast
    soundings indicate profiles supportive of at least weak to moderate
    CAPE, even as the boundary-layer becomes hot and deeply mixed with
    40-50F+ surface temperature/dew point spreads by peak afternoon
    heating.

    Initially more modest late afternoon instability in the lower
    deserts around Phoenix may gradually destabilize with boundary-layer
    moistening after sunset, eventually supporting the propagation of
    convection into/across the Greater Phoenix area by late evening.
    Details of the potential convective evolution remain uncertain, but
    at least some model output suggest the evolution of a substantive
    convective cluster is possible, which could become accompanied by
    more widespread strong to severe gusts.

    ..Kerr.. 08/18/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Wed Aug 19 05:46:56 2026
    ACUS02 KWNS 190546
    SWODY2
    SPC AC 190544

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1244 AM CDT Wed Aug 19 2026

    Valid 201200Z - 211200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
    THE NORTHERN PLAINS...THE MID SOUTH...AND THE MID ATLANTIC...

    ...SUMMARY...
    Scattered severe storms are possible Thursday across parts of the
    Mid Atlantic, from Nebraska into Wisconsin, and over parts of the
    Mid South.

    ...From NE into northwest WI...
    Mid to upper level northwest winds will increase across the region,
    with 30-40 kt at 500 mb common. At the surface, low pressure will
    develop into northern MN with a cold front extending southwestward
    across eastern SD and into northern NE by 00Z.

    Although high pressure will exist east of this area, pockets of 60s
    dewpoints will still exist ahead of the front, and, temperatures
    aloft will be cool. Daytime heating will thus support
    destabilization along the front, with scattered storms from
    northeast MN/northern WI into NE. Favorable deep-layer shear around
    40 kt along with the cool air aloft will support cells capable of
    hail. Isolated hail near 2.00" cannot be ruled out over NE, but this
    will depend on actual moisture return and potential for stronger
    than forecast instability.

    ...Mid Atlantic...
    Weak low pressure is forecast to translate eastward along a front
    which will move into southern PA/central NJ, while another surface
    low develops into eastern VA/northeast NC with a increasing
    convergence there. Across this small warm sector, upper 60s to 70s F
    dewpoints will lead to a zone of moderate instability, and scattered
    storms should develop from southeast PA/NJ into MD, DE, and eastern
    VA. Additional activity may develop southwestward into northern NC.
    20-30 kt mean winds above 700 mb will support clusters of cells
    moving southeastward during the late afternoon, with strong to
    locally severe wind gusts possible. Isolated marginal hail cannot be
    ruled out as upper level temperatures will be cool.

    ...Mid South...
    A surface trough will develop from the Red River eastward across AR
    and into northern MS, with a weak wind shift providing a focus for
    storm development. CAM guidance continues to show a cluster of
    storms developing after 21Z over northern MS into southwest TN. The
    environment will be very warm and moist, with temperatures near 100
    F and precipitable water values near 2.00". Shear will be weak, and
    storms are likely to produce strong outflow winds, possibly severe
    downbursts. Isolated marginal hail cannot be ruled out as
    temperatures aloft will be relatively cool.

    ..Jewell.. 08/19/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Wed Aug 19 17:14:02 2026
    ACUS02 KWNS 191713
    SWODY2
    SPC AC 191712

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1212 PM CDT Wed Aug 19 2026

    Valid 201200Z - 211200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
    MID-ATLANTIC...AND PARTS OF NEBRASKA INTO SOUTHERN MINNESOTA AND
    NORTHWEST WISCONSIN...

    ...SUMMARY...
    Scattered severe storms are possible Thursday across parts of the
    Mid Atlantic, posing a risk for damaging wind gusts. Large hail and
    isolated wind damage will be possible with severe storms from
    Nebraska into northwest Wisconsin.

    ...Mid-Atlantic...

    A midlevel shortwave impulse is forecast to spread eastward from the
    Ohio Valley to the Mid-Atlantic through Thursday evening. This will
    result in enhanced southwesterly flow atop a very moist boundary
    layer. Strong heating along/east of a surface trough oriented from
    northern MD through central VA/NC will support a corridor of
    moderate destabilization. Thunderstorms are expected to develop near
    a warm front across southern/central NJ south/southwest along the
    surface trough into central/eastern VA/NC during the afternoon.
    Effective shear magnitudes around 40 kt will support organized
    cells, perhaps becoming linear segments with time. Damaging wind
    gusts will be possible, supported further by steep low-level lapse
    rates and high PW values. The strongest cells could also produce
    hail.

    ...TN Valley/Southeast...

    A surface tough will extend southwestward from the NC Piedmont into
    northern MS/central AR Thursday afternoon. A seasonally moist and
    hot airmass will be in place, fostering moderate to strong
    instability. Weak convergence along the surface boundary will
    promote scattered thunderstorm development. Vertical shear will be
    weak, but thunderstorm clusters could produce damaging outflow gusts
    with the steep lapse rates/high PW environment. Forecast soundings
    also show so cooler temperature aloft, and isolated hail could
    accompany strong storms across parts of northern MS and the TN
    Valley.

    Further south into central/southern AL, southwest GA and the FL
    Panhandle vicinity, isolated cells are expected within a similar
    environment, but even weaker deep-layer flow is forecast.
    Nevertheless, sporadic wet microbursts will be possible, posing a
    risk for locally damaging gusts.

    ...Central Plains to MN/WI...

    Northwesterly flow aloft will increase Thursday afternoon into
    evening. At the surface, weak low pressure will migrate east across
    northern MN toward the U.P. of MI. As this occurs, a weak surface
    front will develop southeast across the region. Ahead of this
    boundary, modest boundary layer moisture will remain in place
    (generally low to maybe mid-60s F dewpoints). Supercell wind
    profiles are evident in forecast soundings, with elongated/straight
    hodographs noted above 2-3 km. Isolated to widely scattered storms
    will develop by late afternoon/early evening, posing a risk for
    large hail and locally damaging winds. With southward extent into
    NE, a narrow corridor may exist for significant hail (greater than 2
    inch diameter) given steep midlevel lapse rates/cool temperatures
    aloft and somewhat higher boundary layer moisture compared to
    further north.

    ...AZ...

    Easterly midlevel flow on the southern periphery of an upper
    anticyclone over the Four Corners will remain in place on Thursday.
    Modest boundary layer moisture will persist over lower elevations
    amid the steep lapse rate environment. This will promote MLCAPE
    around 1000-1250 J/kg. Thunderstorms will develop over higher
    terrain during the late afternoon. Damaging wind potential will
    increase as storms consolidate and propagate westward over the lower
    elevations of central/southern AZ during the evening.

    ..Leitman.. 08/19/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Thu Aug 20 05:45:48 2026
    ACUS02 KWNS 200545
    SWODY2
    SPC AC 200543

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1243 AM CDT Thu Aug 20 2026

    Valid 211200Z - 221200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
    NEBRASKA AND INTO NORTHERN KANSAS...

    ...SUMMARY...
    Scattered damaging hail (some greater than 2 inch diameter) and
    severe wind gusts may occur over parts of the central Plains late
    Friday afternoon and evening. Scattered storms, some with severe
    wind gusts, are possible Friday afternoon over parts of the
    Carolinas and Georgia.

    ...NE into northern KS...
    Moderate northwest flow aloft will develop over the northern to
    central Plains on Friday, as a surface trough develops over the High
    Plains. This will result in directional shear with elongated
    hodographs featuring 50 kt effective deep-layer shear. Storms are
    expected to develop near the low-level lapse rate plume during the
    late afternoon over central to western NE, with cells moving
    southeastward into the mid 60s F dewpoints and producing very large
    hail. Isolated significant wind gusts may also occur if
    storms/outflows merge, possibly extending into northern KS during
    the evening. Overall storm coverage is uncertain, but at least
    scattered cells appear likely, with high conditional risk of severe
    hail/wind.

    ...Carolinas...GA...
    A very moist and unstable air mass is forecast over the region on
    Friday, near a surface trough and south of a cold front pushing into
    NC. Numerous storms are forecast to develop after 20Z, within a weak shear/strong instability environment. MLCAPE is forecast to be over
    3000 J/kg, supporting vigorous updrafts and locally severe
    microbursts and outflows.

    ..Jewell.. 08/20/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Thu Aug 20 17:24:42 2026
    ACUS02 KWNS 201724
    SWODY2
    SPC AC 201722

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1222 PM CDT Thu Aug 20 2026

    Valid 211200Z - 221200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE CENTRAL PLAINS...

    ...SUMMARY...
    Scattered damaging hail (some greater than 2 inch diameter) and
    severe wind gusts may occur over parts of the central Plains late
    Friday afternoon and evening. Scattered storms, some with severe
    wind gusts and hail, also are possible across parts of the Midwest
    and Southeast.

    ...Central Plains...

    Enhanced northwesterly flow aloft will overspread portions of the
    region on Friday. Meanwhile, a plume of steep midlevel lapse rates
    will shift east across the central Plains toward the Mid-MO Valley.
    A corridor of rich boundary layer moisture will be in place within east/southeast low-level flow across portions of KS/NE ahead of a
    west-to-east oriented surface boundary. Moderate to strong
    instability is forecast by late afternoon into evening, supporting
    widely scattered thunderstorm development near the surface boundary.
    Vertically veering wind profiles with elongated/straight hodographs
    and 45+ kt effective shear magnitudes will support initial
    supercells. Large to very large hail (some greater than 2 inches
    diameter) will be possible. With time, a forward propagating cluster
    could develop and move southeast across parts of NE and KS. Some
    potential for severe gusts (a few near 70-80 mph) will be possible
    given large instability and steep low-level lapse rates.

    It is uncertain how far south the severe risk will persist into the
    overnight hours. Forecast guidance, including CAMs, vary
    considerably, but some potential could spread into parts of northern
    OK late Friday/early Saturday. For now, have extended the Marginal
    risk southward across KS to account for conditional severe
    potential.

    ...IA/WI/IL...

    Northwesterly flow aloft will modestly increase on Friday as an
    upper trough deepens over the Midwest. Cooling aloft will also
    result in areas of steepening midlevel lapse rates atop a seasonally
    moist airmass ahead of a southeastward-advancing cold front. This
    will aid in a corridor of moderate to strong destabilization across
    portions of IA into northern IL and southern/eastern WI. Vertical
    wind profiles will support supercell thunderstorms capable of large
    hail and strong wind gusts. The southward extent of the risk into
    central IL is a bit uncertain, but some risk could persist into late
    evening.

    ...Southeast/Carolinas...

    A very moist and strongly unstable airmass will be in place in the
    vicinity of a surface trough Friday afternoon. Strong heating and
    weak confluence will aid in thunderstorm development along the
    surface trough and higher terrain. Sufficient storm coverage could
    result in clustering/forward propagating as storms move eastward
    through the afternoon/early evening. Otherwise, weak vertical shear
    will limit overall organization, but sporadic severe/damaging gusts
    could occur from wet microbursts within the unstable/high PW
    airmass.

    ..Leitman.. 08/20/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Fri Aug 21 05:50:18 2026
    ACUS02 KWNS 210550
    SWODY2
    SPC AC 210548

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1248 AM CDT Fri Aug 21 2026

    Valid 221200Z - 231200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR NORTHERN
    IDAHO AND WESTERN MONTANA...THE CENTRAL HIGH PLAINS...ARKANSAS AND VICINITY...AND THE OHIO VALLEY...

    ...SUMMARY...
    Strong to severe thunderstorms capable of wind gusts and isolated
    large hail will be possible in the Ohio Valley and Arkansas
    vicinity. Severe gusts are possible across the central High Plains
    and northern Idaho into western Montana.

    ...Northern Idaho and western Montana...
    A strong mid-level shortwave trough will move into the Northwest on
    Saturday with modest diffluence ahead of it during the day. Strong
    heating should result in steep lapse rates and weak instability
    across the region. Storms should develop over the mountains by
    midday and advance northeast. As 6km flow strengthens to ~40 knots
    by mid-afternoon, adequate shear should be in place for a few
    organized storms. The steep lapse rates and inverted-v thermodynamic
    profile will support severe wind gusts as the primary threat.

    ...Central High Plains...
    Diurnal, terrain driven thunderstorms will develop by early
    afternoon and eventually move into the adjacent Plains by late afternoon/evening. Forecast soundings show moderate to potentially
    strong instability across the Plains with moderately steep lapse
    rates and dewpoints perhaps into the low 60s. The primary limiting
    factor will be shear with less than 30 knots of flow below 300mb.
    However, enough flow should be present, when combined with the
    moderate to strong instability, to support some storms capable of
    severe wind gusts.

    ...Arkansas and Vicinity...
    The most favorable environment across the CONUS on Saturday appears
    to be from eastern Kansas to Arkansas beneath a belt of stronger
    mid-level flow where moderate to strong instability may also be in
    place. This environment would even support supercells. However,
    storm coverage remains uncertain. Added a small 5% in the Arkansas
    vicinity where at least isolated storms appear most likely. However,
    with relatively nebulous forcing, perhaps related to remaining
    convection from Friday, confidence is low where the strongest storms
    may occur.

    ...Ohio Valley...
    A mid-level shortwave trough will amplify across the Great Lakes on
    Saturday and become negatively tilted toward the end of the period.
    As this occurs, a surface low will deepen somewhat across southern
    Ontario with a cold front sweeping across Ohio and northern Kentucky
    through the day. Despite relatively weak heating across the region
    due to extensive cloud cover, moderate instability is forecast to
    develop amid upper 60s dewpoints and cooling temperatures aloft.
    This, combined with 25 to 30 knots of shear, should be sufficient
    for multicells and occasional supercells capable of primarily
    damaging wind gusts.

    ..Bentley.. 08/21/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Fri Aug 21 17:28:32 2026
    ACUS02 KWNS 211728
    SWODY2
    SPC AC 211726

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1226 PM CDT Fri Aug 21 2026

    Valid 221200Z - 231200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SATURDAY INTO
    SATURDAY EVENING ACROSS PARTS OF THE NORTHERN INTERMOUNTAIN REGION
    INTO NORTHERN ROCKIES...THE FRONT RANGE INTO CENTRAL GREAT
    PLAINS...THE SOUTHEASTERN GREAT PLAINS...MIDDLE/UPPER OHIO VALLEY
    AND ADJACENT LOWER GREAT LAKES REGION...

    ...SUMMARY...
    Scattered strong storms may impact a corridor from near the northern
    Rockies into the southeastern Great Plains, as well as the middle
    and upper Ohio Valley vicinity, Saturday. These may pose at least
    some potential to produce severe wind and hail.

    ...Discussion...
    Models indicate that the increasingly deformed remnants of a
    mid-level low will be forced inland across the northern U.S. Pacific
    coast during this period, with a still vigorous remnant perturbation approaching the Canadian/northern U.S. Rockies by late Saturday
    night. Downstream, the center of a prominent mid-level ridge is
    forecast to slowly shift across and east of the southern Rockies,
    with amplified ridging within the westerlies to the north
    overspreading much the Canadian Prairies and northern U.S. Great
    Plains.

    To the east of this ridging, it appears that large-scale troughing
    will undergo further amplification across areas east of the
    Mississippi Valley through the Atlantic Seaboard. Within this
    regime, guidance indicates that one vigorous short wave impulse will
    dig southeast of the Upper Midwest/adjacent Great Lakes through the
    upper Ohio Valley by late Saturday night, trailed by a similar
    strength impulse across northwestern Ontario toward the northern
    Great Lakes vicinity. These are likely to be preceded by at least a
    couple of increasingly sheared perturbations, including one
    generally forecast to accelerate northeastward offshore of the
    southern Mid Atlantic coast early in the period.

    Near the southwestern flank of the larger-scale troughing, a
    convectively generated or augmented perturbation might maintain
    strength within modest north-northwesterly flow, around the eastern
    periphery of the stronger mid-level ridging, across the southeastern
    Great Plains toward northwestern Gulf coast.

    In lower-levels, it appears that the leading edge of a series of
    surges of cooler air, probably reinforced by convective outflow
    across at least portions of the Great Plains, may reach central
    Texas and northern portions of the remainder of the Gulf Coast into
    southern Mid Atlantic Seaboard by 12Z Sunday. This is expected in
    the wake of a modestly deepening surface low to the north of the
    lower Great Lakes, and a weaker secondary low developing
    near/offshore of the Mid Atlantic.

    ...Ohio Valley into lower Great Lakes region...
    In advance of the vigorous lead digging short wave trough, and an
    associated influx of surface cooling, a corridor of low-level
    moistening may contribute to potential for moderate boundary-layer destabilization by late afternoon. It appears that this will have
    to occur in the wake of early period warm advection driven
    convective cloud cover and precipitation likely to overspread the
    region. However, breaks in the cloud cover and the onset of cooling
    aloft may become sufficient to support scattered vigorous
    thunderstorm development. Despite generally modest to weak vertical
    shear, modest steepening of lower into mid-level lapse rates of
    temperature and potential wet-bulb temperature may be sufficient to
    contribute to profiles conducive to localized downbursts, in
    addition to marginally severe hail.

    ...Front Range into southeastern Great Plains...
    Latest convection-allowing guidance and other model output remains
    rather varied concerning the potential evolution of storms and the
    associated risk for severe weather through this period. However,
    there do appear at least a couple of corridors with a somewhat
    higher likelihood for thunderstorm initiation and organization
    Saturday through Saturday night.

    One may develop on the eastern periphery of the mid-level high
    across the southeastern Great Plains, where stronger
    lower/mid-tropospheric warm advection may focus near the nose of an increasingly suppressed plume of elevated mixed-layer air. Wind fields/vertical shear may be modest to weak, but a corridor of
    higher low-level moisture content may support storm inflow with
    large CAPE ahead of a remnant convective perturbation, supporting
    potential for the evolution of an intensifying and organizing south/southwestward propagating storm cluster with risk for severe
    hail and wind.

    Another may focus in moistening upslope flow along/east of the
    Laramie mountains through Colorado Front Range by late Saturday
    afternoon. Perhaps aided by a weak short wave impulse slowly
    pivoting across this region, around the periphery of the mid-level
    high, convection may consolidate into an intensifying and organizing
    cluster propagating into the adjacent Great Plains by Saturday
    evening, aided by updraft inflow of air characterized by moderately
    large CAPE.

    ...Eastern Idaho into western Montana...
    Multiple waves of scattered thunderstorm development appear possible
    across the region Saturday into Saturday night, ahead of the inland
    advancing short wave trough. In the wake of an initial round of overnight/early period convection, models suggest that boundary
    layer moistening will be sufficient to support increasing, though
    still rather modest to weak, CAPE with heating and deep mixing by
    late Saturday afternoon. Still, thermodynamic profiles may become
    conducive to a few localized downbursts into Saturday evening.

    ..Kerr.. 08/21/2026

    $$

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  • From COD Weather Processor @1:2320/107 to All on Sat Aug 22 05:59:26 2026
    ACUS02 KWNS 220559
    SWODY2
    SPC AC 220557

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1257 AM CDT Sat Aug 22 2026

    Valid 231200Z - 241200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
    EASTERN GREAT LAKES INTO THE NORTHEAST...THE NORTHERN PLAINS...AND
    MONTANA....

    ...SUMMARY...
    Strong thunderstorm activity posing at least some risk for severe
    hail and wind appears possible across parts of the northern Rockies
    and Great Plains, and across parts of the eastern Great Lakes to the
    Northeast, Sunday through Sunday night.

    ...Montana...
    A deamplifying mid-level shortwave trough will move from the Pacific
    Northwest into eastern British Columbia on Sunday. As this occurs, a
    lee cyclone across Montana will advect moisture northwestward into
    central Montana with some 60F dewpoints expected. Moderate mid-level
    flow along the southern periphery of this mid-level trough will
    overspread a weak to moderately unstable airmass across Montana. The
    majority of the forcing will be farther north across Canada,
    however, weak height falls and terrain driven circulations should be
    sufficient enough for storm development by mid-afternoon across
    central Montana. 30 to 35 knots of shear should be sufficient for
    storm organization including some supercell potential. In addition,
    strong heating will result in steep lapse rates and an environment
    supporting damaging winds.

    ...Dakotas...
    Moderate to potentially strong instability is forecast across
    central South Dakota and vicinity on Sunday afternoon, southwest of
    a frontal zone. Persistent southwesterly 1km flow is expected for
    much of the day. Isentropic ascent within this zone will support the
    potential for thunderstorms for much of the day. Thunderstorm coverage/intensity may increase as a mid-level shortwave trough
    approaches the region during the afternoon. In addition, the
    low-level jet is expected to strengthen during the evening which
    will result in more widespread storm development. The environment,
    featuring moderate to strong instability and 35-45 kts of effective
    shear, within a zone of moderate forcing, may result in some strong
    storms capable of large hail and severe wind gusts.

    ...Eastern Great Lakes into the Northeast...
    A strong mid-level trough across the Great Lakes will become a
    closed upper low across southern Ontario on Sunday. An individual
    mid-level trough revolving around the primary trough will become
    negatively tilted as it pivots through the Northeast. A secondary
    mid-level shortwave trough will dig into the western portion of this
    trough and emerge around the base of the trough late Sunday evening.
    These features amid the deepening upper low will result in
    persistent ascent across the region where weak instability will also
    be present. Shear may be relatively weak (20 to 25 knots), which may
    limit overall storm organization. However, the cool temperatures
    aloft should be sufficient for isolated large hail and damaging wind
    gusts.

    ...Arkansas and Vicinity...
    Most guidance shows a moderate low-level jet and isentropic ascent
    across eastern Oklahoma and into Arkansas late Sunday night and
    early Monday. Forecast soundings, other than the HiRes NAM, show
    relatively meager instability. Therefore, while thunderstorms are
    likely along this zone given the strong forcing, severe storms may
    struggle amid relatively weak instability. Therefore, no
    probabilities have been added at this time.

    ..Bentley.. 08/22/2026

    $$

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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sat Aug 22 17:33:06 2026
    ACUS02 KWNS 221732
    SWODY2
    SPC AC 221730

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1230 PM CDT Sat Aug 22 2026

    Valid 231200Z - 241200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
    CENTRAL AND EASTERN MONTANA AND PARTS OF THE EASTERN GREAT BASIN
    INTO THE CENTRAL ROCKIES...

    ...SUMMARY...
    Strong thunderstorm activity posing at least some risk for severe
    hail and wind appears possible across parts of the northern Rockies
    and Great Plains, and across parts of the eastern Great Lakes to the
    Northeast, Sunday through Sunday night.

    ...Synopsis...
    Upper ridging will prevail across the western CONUS as an upper
    trough slowly traverses the Northeast tomorrow (Sunday). A mid-level
    impulse will crest the upper ridge tomorrow afternoon across the
    northern Rockies while a small impulse embedded in the
    aforementioned upper trough overspreads the northern Appalachians.
    From the northern Rockies to northern High Plains, as well as parts
    of the Northeast, stronger flow above the boundary layer will
    promote adequate vertical wind shear, in tandem with buoyancy, to
    promote strong to severe thunderstorms. Elsewhere from the central
    Rockies to the Gulf/Carolina coastlines, strong surface heating amid
    pockets of low-level moisture will support scattered thunderstorm
    development, with an isolated severe storm possible.

    ...Northern Rockies...
    By mid to late afternoon, a well-mixed boundary layer should develop
    beneath a plume of cooler temperatures aloft (e.g. 8+ C/km mid-level
    lapse rates) with the passage of the aforementioned mid-level
    impulse. A belt of stronger mid- to -upper level westerly flow will
    also accompany this impulse, resulting in elongated hodographs and
    30-40 kts of effective bulk (speed) shear coinciding with the steep
    low- and mid-level lapse rates. Multicells and transient supercells
    should develop, accompanied by a risk of severe gusts and perhaps an
    instance or two of hail. A gust over 75 mph is possible.

    ...Northern High Plains into South Dakota...
    Convective evolution and morphology remains unclear in this region.
    Steep lapse rates will emanate from the northern Rockies and
    overspread a moistening warm sector (e.g. mid 60s F dewpoints),
    yielding 2000+ J/kg MLCAPE. Modestly curved and elongated hodographs
    suggest multicells and supercells as the main storm mode, at least
    initially. Severe gusts/hail would accompany these storms if they
    can become sustained. There is also some indication by the latest
    CAMS that storms may merge into a cold-pool-driven MCS, though
    guidance consensus is weak on this scenario. Nonetheless, any MCS
    development that does occur would support severe gusts, including a
    75+ mph gust.

    ...Portions of the eastern Great Basin to the central Rockies...
    A cluster of multicell storms should develop around the eastern
    Great Basin into the central Rockies by afternoon peak heating.
    Stronger flow aloft will glance the region to the north, atop a
    strongly mixed boundary layer. Forecast soundings show classic
    inverted-V profiles extending to 500 mb, with surface-500 mb lapse
    rates reaching at least 9 C/km. As such, severe gusts are possible
    with the stronger multicells that form.

    ...Portions of the Northern Appalachians into New England...
    By afternoon, surface temperatures should warm well into the 70s F
    as earlier showers and thunderstorms make way for at least partly
    clearing skies. While not overly steep, mid-level lapse rates
    exceeding 6.5 C/km will result in marginal buoyancy, amid stronger
    flow aloft (yielding elongated hodographs). A couple instances of
    damaging gusts/hail will be possible with the stronger multicells
    that manage to sustain themselves.

    ...Gulf to Carolina Coastlines...
    A heated and moist boundary layer should develop by afternoon given
    the presence of mid 70s F surface dewpoints and temperatures rising
    well into the 80s F. Such rich low-level moisture will support
    2000-4000 J/kg MLCAPE from LA to extreme eastern NC despite
    mid-level lapse rates only reaching 6-6.5 C/km. Across the Gulf
    Coast, pulse-cellular storms are expected given weak flow aloft,
    with damaging gusts originated from wet downbursts the main threat.
    Along the Carolina Coastline, southwesterly mid-level flow will be a
    bit stronger given the upper trough glancing by to the north.
    Multicells capable of isolated severe gusts are possible. Locally
    higher severe probabilities may be needed in future Day 1 outlooks
    if greater storm coverage becomes apparent.

    ...Portions of southern Arizona...
    Locally stronger southeasterly mid-level flow will pivot around the
    upper ridge and overspread a deep and dry boundary layer by late afternoon/early evening. Meanwhile, surface temperatures around 100
    F, amid 60 F surface dewpoints and overspread by modestly cooler
    temperatures aloft, will yield 9+ C/km tropospheric lapse rates and
    over 2000 J/kg MLCAPE. Given the modest flow aloft and
    aforementioned buoyancy, a few organized multicells may occur,
    accompanied by an isolated severe gust threat.

    ..Squitieri.. 08/22/2026

    $$

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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sun Aug 23 05:53:36 2026
    ACUS02 KWNS 230553
    SWODY2
    SPC AC 230551

    Day 2 Convective Outlook
    NWS Storm Prediction Center Norman OK
    1251 AM CDT Sun Aug 23 2026

    Valid 241200Z - 251200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
    THE NORTHERN GREAT BASIN INTO THE CENTRAL HIGH PLAINS AND THE
    NORTHERN PLAINS...THE SOUTHEAST...AND NORTHERN MAINE...

    ...SUMMARY...
    Thunderstorms with at least isolated severe gusts/hail are possible
    across the northern Great Basin to the High Plains and northern
    Plains Monday afternoon and evening. A couple of damaging gusts may
    also occur with storms in Maine and along parts of the Gulf Coast to
    the eastern Carolinas.

    ...Northern Plains...
    A mid-level shortwave trough will traverse the Canadian prairies on
    Monday with some weak height falls overspreading North Dakota and
    northern South Dakota. A weak surface low will accompany this trough
    with a cold front extending into the Dakotas. Moderate to
    potentially strong instability is forecast ahead of this cold front.
    Subtle forcing from the height falls and weak convergence along the
    front may support isolated storms during the afternoon/evening.
    Long/straight hodographs would support supercells capable of large
    hail and severe wind gusts. Steep lapse rates will support some
    potential for 75+ mph wind gusts. In addition, if any longer lived
    supercells can develop, 2+ inch hail is also possible. Stronger
    forcing, hinted at by the more amplified mid-level trough on the 00Z
    NAM, would support greater storm coverage and potentially greater
    hail/wind probabilities in later outlooks.

    ...Northern Great Basin into the central High Plains...
    Widely scattered storms are forecast to develop over the higher
    terrain from the northern Great Basin to the central Rockies. As
    storms move into the adjacent Plains, where strong heating and steep
    lapse rates are forecast, severe wind gusts are possible. Storm mode
    will be single cell to multicell, with only 15 to 25 knots of shear
    across the region. However, the thermodynamic profile will support
    an isolated severe wind threat.

    ...Southeast...
    Temperatures in the mid to upper 80s amid mid 70s F dewpoints will
    yield MLCAPE over 2000 J/kg from Louisiana to the North Carolina
    coast. Despite weak tropospheric flow, enough moisture-fueled
    buoyancy will support the potential for wet downbursts capable of
    damaging gusts during the afternoon.

    ...Maine...
    Deep-layer ascent ahead of an ejecting mid-level shortwave trough
    will support scattered thunderstorm development during the late
    morning into the afternoon hours across central and northern Maine.
    A belt of 60 kt 500 mb southwesterly flow will pivot around the
    upper trough and overspread Maine during the afternoon, when
    buoyancy will be maximized. MLCAPE may exceed 750 J/kg with over 50
    kts of effective bulk/speed shear. Therefore, any storms that
    develop may become multicellular or transient supercellular in
    nature, posting an isolated damaging gust/hail threat through the
    afternoon.

    ..Bentley.. 08/23/2026

    $$

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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)