• DAY1 2/5 Risk Areas Poste

    From Mike Powell@618:250/1 to All on Thu Jul 17 08:52:26 2025
    ACUS01 KWNS 171237
    SWODY1
    SPC AC 171235

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0735 AM CDT Thu Jul 17 2025

    Valid 171300Z - 181200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE NORTHEAST AND NORTHERN HIGH PLAINS...

    ...SUMMARY...
    Scattered damaging winds and a brief tornado are possible across
    northern New England this afternoon. Isolated/sporadic damaging
    winds may also occur across a broad swath of the
    Northeast/Mid-Atlantic to the southern High Plains. A confined
    corridor of large hail and severe gusts appears possible from
    north-central Montana to southwest North Dakota this evening.

    ...Northeast...
    The Slight Risk has been maintained across this region with no
    changes. A shortwave trough will move northeastward from the Upper
    Great Lakes to the Ontario/Quebec border vicinity by this evening. A
    broad swath of enhanced 850-700 mb west-southwesterly winds is
    forecast from PA/NJ northward into New England. Further weakening of
    already poor mid-level lapse rates is anticipated across parts of
    southern NY into southern New England. This may tend to limit
    convective coverage across the northern Mid-Atlantic to southern New
    England vicinity. But, farther north and in closer proximity to
    ascent associated with the approaching mid-level shortwave trough,
    scattered robust convection is anticipated this afternoon along the
    Quebec border across northern New England. Sufficient instability
    and deep-layer shear are forecast across this region to support a
    mix of multicells and perhaps marginal supercells. Given the
    enhanced low/mid-level flow, scattered damaging winds should be the
    main threat with this activity as it moves generally
    east-northeastward through the early evening, before eventually
    weakening as it approaches the coast. Enough low-level hodograph enlargement/curvature may also be present to support some risk for a
    tornado or two.

    ...Mid-Atlantic to the Southern High Plains...
    Extensive convection is ongoing this morning across
    south-central/southeast KS into MO. This activity should generally
    remain sub-severe, but it will help reinforce a front that is
    expected to gradually sag southward and eventually stall across the
    mid MS Valley to southern Plains today. Scattered to numerous
    thunderstorms are expected to develop west of the Appalachians along
    this boundary later this afternoon as diurnal heating occurs.
    Moderate to strong instability amid steepened low-level rates
    along/south of the outflow/front should support sporadic wet
    microbursts. Isolated hail will be possible with thunderstorms in
    the post-frontal upslope flow regime across parts of the southern
    High Plains. But, modest deep-layer shear and warm temperatures
    aloft across all these regions should temper the overall
    intensity/coverage of severe convection. Isolated damaging winds may
    also occur with thunderstorms that develop east of the central
    Appalachians this afternoon, even though coverage should be somewhat less.

    ...Northern Plains...
    A narrow corridor of supercell potential remains evident across
    north-central MT to southwest ND, mainly this evening. A positively
    tilted mid-level shortwave trough over the southern Canadian Rockies
    will progress eastward along the international border with MT/ND
    today. Mid to late afternoon convective initiation should occur over
    parts of southwest Alberta in association with this feature. A
    confined plume of weak buoyancy ahead of this activity should
    initially temper updraft intensity as it spreads east-southeastward
    into north-central MT by late afternoon. But, favorably timed
    strengthening of a 500-mb westerly jet over MT will aid in hodograph
    elongation at mid/upper levels this evening. This could support a
    long-lived supercell or two during the evening, impinging on the
    nose of moderate instability that should be present across southeast
    MT. Large hail should be the main threat with these supercells if
    they can be maintained. An isolated hail/wind risk may persist along
    the ND/SD border vicinity overnight.

    ..Gleason/Bentley.. 07/17/2025

    $$
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  • From Mike Powell@618:250/1 to All on Fri Jul 18 09:58:14 2025
    ACUS01 KWNS 181244
    SWODY1
    SPC AC 181243

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0743 AM CDT Fri Jul 18 2025

    Valid 181300Z - 191200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF VIRGINIA/NORTH CAROLINA...AND PARTS OF CENTRAL/EASTERN
    NEBRASKA...SOUTHEAST SOUTH DAKOTA...SOUTHWEST MINNESOTA...AND
    WESTERN/CENTRAL IOWA...

    ...SUMMARY...
    Scattered severe thunderstorms with large hail, damaging winds, and
    a few tornadoes are possible across parts of the Corn Belt in Iowa,
    Minnesota, Nebraska, and South Dakota this evening into tonight.
    Scattered damaging winds are possible across parts of Virginia and
    North Carolina this afternoon.

    ...Virginia/North Carolina to the Mid-South...
    A generally west-east oriented quasi-stationary front reinforced by
    outflow from earlier convection should serve as a low-level forcing
    mechanism for thunderstorm development this afternoon from parts of
    VA/NC westward to the Mid-South and vicinity. A seasonably moist
    airmass will be present today along/south of this front, with
    surface dewpoints generally ranging from the upper 60s in higher
    elevations to mid 70s elsewhere. Even though mid-level lapse rates
    are expected to remain rather modest, ample daytime heating of the
    moist low-level airmass will contribute to sizable MLCAPE by early
    to mid afternoon. With a subtropical anticyclone centered off the
    Southeast Atlantic Coast and stronger flow aloft associated with
    various mid-level perturbations expected to remain over the Great Lakes/Northeast, large-scale ascent in the vicinity of the surface
    front will be nebulous at best.

    Regardless, scattered to numerous thunderstorms should develop
    along/near this boundary through the afternoon, while spreading
    generally eastward this evening. With modest mid-level westerly flow
    forecast, deep-layer shear appears marginal for thunderstorm
    organization. The greatest threat for scattered damaging winds
    should focus across parts of VA/NC this afternoon and early evening,
    where semi-organized clusters and short line segments appear
    possible given slightly stronger deep-layer shear. Otherwise,
    isolated damaging winds may occur even with less organized
    convection farther west towards parts of the TN Valley/Mid-South, as
    steepened low-level lapse rates potentially support microbursts.
    There does appear to be a gap in scattered convective coverage
    across parts of MO and vicinity, where the Marginal Risk has been
    removed with this update.

    ...South Dakota/Nebraska into Minnesota/Iowa...
    Elevated convection across parts of SD may continue to pose an
    isolated hail threat this morning, before it eventually weakens with
    the gradual lessening of a southerly low-level jet. A belt of strong
    westerly mid-level flow will remain in place over the northern tier
    of the CONUS from MT eastward towards the Great Lakes. Gradual
    low-level moistening is forecast through this evening ahead of a
    weak front forecast to be in place over the eastern Dakotas into
    western NE. Diurnal heating and modestly steepened mid-level lapse
    rates will contribute to moderate to strong MLCAPE across parts of
    NE/southeast SD into IA. But, nebulous forcing for ascent and
    residual capping should tend to suppress surface-based convective
    development across these areas for much of the day. Occasional
    severe hail may occur with mainly elevated convection to the north
    of the front in MN.

    A gradually strengthening southerly low-level jet this evening
    (mainly after 00Z) should aid in convective initiation along/near
    the front from central/northeast NE into southeast SD/southwest MN.
    Various NAM/RAP forecast soundings across this region suggest ample
    instability and strong deep-layer shear will be present to support
    supercells with attendant large hail threat initially. Low-level
    shear should also be strong enough for a tornado threat with these
    supercells, although there may be a fairly narrow spatial/temporal
    window for convection to remain discrete this evening. Upscale
    growth into a bowing cluster should occur through mid to late
    evening, with a threat for mainly scattered severe/damaging winds as
    this convection tracks into parts of IA overnight, before eventually
    weakening early Saturday morning.

    ...Great Basin into Wyoming and Far Southern Montana...
    Initially high-based convection should develop this afternoon across
    parts of the Great Basin into WY as modest ascent associated with a weak/low-amplitude mid-level impulse spreads eastward across these
    areas. While low-level moisture and deep-layer shear will remain
    limited, steepened low/mid-level lapse rates amid a very well-mixed
    boundary layer should support isolated severe gusts with any
    thunderstorms that can be sustained amid weak instability. Somewhat
    greater low-level moisture should be present this afternoon across
    parts of southern MT into northern/eastern WY, generally along/east
    of the Bighorn/Laramie Mountains. Isolated severe hail may occur
    with marginal supercells given greater instability/shear forecast
    across these areas.

    ..Gleason/Bentley.. 07/18/2025

    $$
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  • From Mike Powell@618:250/1 to All on Sat Jul 19 09:08:50 2025
    ACUS01 KWNS 191246
    SWODY1
    SPC AC 191245

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0745 AM CDT Sat Jul 19 2025

    Valid 191300Z - 201200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE NORTHERN/CENTRAL PLAINS...MIDWEST/GREAT LAKES...AND
    VIRGINIA/NORTH CAROLINA...

    ...SUMMARY...
    Scattered damaging winds are possible today across parts of the
    Midwest/Great Lakes and southern Mid-Atlantic. Scattered large to
    very large hail and severe gusts are possible across the
    northern/central Plains during the late afternoon and evening.

    ...Midwest/Great Lakes...
    A small thunderstorm cluster ongoing this morning across
    southern/eastern IA should continue to track east-southeastward
    along an instability gradient across parts of northern MO, IL, and
    perhaps IN into at least the early afternoon. With sufficient
    organization and evidence of a cold pool, this cluster may pose a
    threat for strong to locally damaging winds. Reference Mesoscale
    Discussion 1719 for more details. The potential for additional
    strong to severe thunderstorms across the Midwest and Great Lakes
    regions remains somewhat unclear given rather nebulous/weak forcing
    aloft. Stronger westerly mid-level flow associated with upper
    troughing over eastern Canada should tend to remain mostly displaced
    to the north of the surface warm sector. Still, daytime heating of a
    moist low-level airmass will likely encourage the development of
    moderate to locally strong instability by early to mid afternoon
    away from convective influences.

    Somewhat stronger flow aloft and related deep-layer shear should be
    present this afternoon across Lower MI. A mix of multicells and
    marginal supercells may spread eastward from ongoing activity across
    WI, or develop separately over this area while posing a threat for
    isolated severe hail and damaging winds. Farther south into the
    Midwest/OH Valley, weaker deep-layer shear and the bulk of
    convection-allowing model guidance suggests that multicell clusters
    should be the main convective mode. One or more of these clusters
    will probably persist from the ongoing activity this morning, or
    develop this afternoon along its outflow. Scattered severe/damaging
    winds will likely be the main threat as these thunderstorms move east-southeastward this afternoon into early evening across much of
    the OH Valley/Midwest. This convection should eventually weaken this
    evening as it encounters a less unstable airmass across the Lower
    Great Lakes and central Appalachians.

    ...Virginia/North Carolina...
    The Mid-Atlantic region will once again reside between upper
    troughing to the north over the Northeast/eastern Canada, and a
    mid/upper-level anticyclone anchored over the Southeast. The primary
    synoptic front remains draped generally east-west along/near the
    MD/PA/DE border. A very moist low-level airmass remains in place to
    the south of this boundary, with surface dewpoints generally in the
    low to mid 70s. A similar convective scenario to yesterday is
    forecast again today. Diurnal heating of this moist airmass will
    likely encourage moderate to locally strong MLCAPE by early
    afternoon, even though mid-level lapse rates are expected to remain
    poor. Around 15-25 kt of mid-level westerly flow should enable
    thunderstorms that initially develop over the Appalachians/Blue
    Ridge to advance eastward towards the lower elevations/coastal
    regions of VA/NC this afternoon and early evening. Scattered
    damaging winds should be the main threat with loosely organized multicells/clusters. Isolated hail may occur with the stronger cores as well.

    ...Northern/Central Plains...
    An upper trough/low is expected to persist today over western
    Canada. On the southern periphery of this feature, a weak mid-level
    shortwave trough should move eastward across the northern
    Rockies/High Plains through this evening. Weaker mid-level westerly
    flow will remain farther south into the central High Plains. At the
    surface, a lee trough will extend southward from eastern MT to
    eastern CO. Generally low to mid 60s surface dewpoints should exist
    this afternoon along/east of the lee trough, with greater low-level
    moisture present near a remnant front/boundary in NE. Isolated
    thunderstorms across northeast MT may pose an isolated hail threat
    this morning. Current expectations are for scattered thunderstorms
    to develop initially over the higher terrain of the northern/central
    Rockies this afternoon, with additional development farther east
    along the lee trough.

    As this convection spreads eastward into a moderately to strongly
    unstable airmass across the northern/central High Plains, it should
    strengthen. Weak low-level winds are forecast to veer and increase
    with height through mid/upper levels, supporting strong deep-layer
    shear and the potential for supercells. Scattered large hail will be
    possible with any supercells that can persist, with most guidance
    indicating a greater concentration of severe thunderstorms across
    eastern MT into western ND, and separately across western/central
    NE. Given the presence of steep mid-level lapse rates and 40-50+ kt
    of deep-layer shear, isolated very large hail appears possible. If
    one or more clusters can develop from the initial supercells, then a
    greater threat for severe gusts would be realized this evening with
    eastward extent across the northern/central Plains. There is low
    confidence in this scenario occurring, however.

    ..Gleason/Bentley.. 07/19/2025

    $$
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  • From Mike Powell@618:250/1 to All on Fri Jul 25 09:18:42 2025
    ACUS01 KWNS 251255
    SWODY1
    SPC AC 251253

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0753 AM CDT Fri Jul 25 2025

    Valid 251300Z - 261200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
    EVENING FOR MUCH OF NORTH DAKOTA...AND FOR PORTIONS OF SOUTHERN NEW
    ENGLAND INTO THE NORTHERN MID-ATLANTIC REGION...

    ...SUMMARY...
    Scattered strong to severe thunderstorms will pose a risk of
    damaging wind gusts across parts of New England and the northern Mid
    Atlantic later today. Severe storms will also be possible across
    much of North Dakota.

    ...Northeast States...
    Morning water vapor imagery shows a fast-moving shortwave trough
    progressing eastward across Ontario. The associated cold front will
    move through the St Lawrence Valley this morning and southward
    across New England this afternoon. Relatively hot/humid conditions
    ahead of the front will lead to widely scattered afternoon
    thunderstorms across southern New England and eastern NY/PA. These
    storms will track southeastward toward the coast through the early
    evening. Coverage of intense storms is uncertain, but conditions
    will be favorable for gusty/damaging winds in the cells that form.

    ...Northern Plains...
    An upper ridge remains centered over the central Plains, with a weak southern-stream trough currently moving across UT into WY. Weak
    lift and increased mid-level moisture ahead of the system will aid
    in the development of scattered thunderstorms by late afternoon
    across parts of eastern MT/northeast WY. Thermodynamic parameters
    appear favorable for large hail in the stronger cells. Model
    guidance varies on handling this activity as it spreads eastward.
    However, it appears reasonable that portions of this early activity
    will persist through the evening and pose a risk of hail and locally
    damaging winds across parts of ND. Later CAM solutions will
    hopefully help better focus this threat area.

    ...KS/MO...
    A large area of overnight convection has resulted in a
    convectively-aided shortwave trough that will move into eastern KS
    this afternoon. Thunderstorms will likely re-develop near/east of
    the remnant MCV and track into western MO during the evening.
    Assuming sufficient heating can occur this afternoon along the
    southeastern edge of the remnant clouds, a corridor of MRGL severe
    threat will likely develop. Isolated damaging wind gusts would be
    the main concern.

    ..Hart/Grams.. 07/25/2025

    $$
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  • From Mike Powell@618:250/1 to All on Thu Jul 31 09:26:06 2025
    ACUS01 KWNS 311238
    SWODY1
    SPC AC 311236

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0736 AM CDT Thu Jul 31 2025

    Valid 311300Z - 011200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
    EVENING OVER PORTIONS OF NORTH-CENTRAL COLORADO AND EASTERN
    WYOMING...AND PARTS OF THE MID ATLANTIC REGION...

    ...SUMMARY...
    A few severe storms capable of damaging winds are possible this
    afternoon across the Mid-Atlantic region. Other severe wind and hail
    producing storms are also possible across the central/northern High Plains.

    ...High Plains...
    A broad upper ridge remains in place across most of the southern US,
    with a weak trough over the western states. A plume of monsoonal
    moisture extends from NM into CO/WY/MT, leading to another round of
    afternoon thunderstorms across the Rockies. The strongest cells
    will pose some risk of hail and gusty winds over the higher terrain
    before spreading onto the plains by late afternoon. Forecast
    soundings in this region show moderately steep mid-level lapse
    rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical
    shear for transient supercell structures. This may be sufficient
    for widely scattered severe storms capable of large hail and
    damaging winds.

    ...Mid Atlantic Region...
    A weak cold front continues to sag southward across parts of PA and
    far southern New England this morning. Strong heating to the south
    of the boundary, coupled with a very moist air mass will lead to
    moderate afternoon MLCAPE values - despite weak mid-level lapse
    rates. Scattered thunderstorms are expected to form along/ahead of
    the front by mid-afternoon. A few severe storms are possible, with
    locally damaging wind gusts being the main concern.

    ...ID/Western MT...
    A shortwave trough is noted in morning water vapor imagery over NV
    lifting northward. Large scale forcing for ascent ahead of the
    trough will foster scattered high-based thunderstorms this afternoon
    across parts of ID and western MT. The strongest cells will be
    capable of gusty/damaging wind gusts.

    ..Hart/Grams.. 07/31/2025

    $$
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  • From Mike Powell@618:250/1 to All on Thu Jul 31 17:44:16 2025
    ACUS01 KWNS 311953
    SWODY1
    SPC AC 311951

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0251 PM CDT Thu Jul 31 2025

    Valid 312000Z - 011200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT
    RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES
    AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING...

    ...SUMMARY...
    Severe thunderstorms capable of damaging winds are possible this
    afternoon and early evening across the Mid-Atlantic region. Other
    severe wind and hail producing storms are also possible across the central/northern High Plains.

    ...20z Update...
    The forecast remains largely on track with only minor adjustments
    made based on recent convective trends. Low-end/5% risk
    probabilities were expanded slightly across portions of the northern
    Rockies where recent observed dewpoint depressions and short-range
    forecast soundings show low-level thermodynamic environments
    favorable for strong/severe downburst winds and GOES imagery shows
    deepening convection. Elsewhere, the forecast remains on track. See
    the previous discussion below and MCDs #1853 and #1854 for
    additional details.

    ..Moore.. 07/31/2025

    .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/

    ...Mid Atlantic Region...
    Midday visible-satellite imagery indicates a moist airmass via a
    swelling cumulus field from the upper OH Valley eastward into the
    Mid-Atlantic states and Long Island. Additional heating of an
    extremely moist boundary layer (12 UTC raobs at IAD and WAL showing
    17-18 g/kg lowest 100-mb mean mixing ratios), will result in
    temperatures warming through the 80s deg F with 74-78 dewpoints to
    the east of the Fall Line.

    An upstream mid-level shortwave trough over WI/IL will continue to
    progress eastward towards the region and promote the gradual
    southward movement of a weak cold front. Despite weak mid-level
    lapse rates, the aforementioned warming/destabilization through mid
    afternoon will promote scattered thunderstorms along/ahead of
    the front. Forecast hodographs will be elongated due to 50-70 kt
    upper-level flow, which will support storm organization in the form
    of multicell clusters and possibly a few weak supercell structures.
    Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered
    50-65 mph gusts capable of wind damage will be the primary severe
    concern before much of this activity moves east of the coast by mid evening.

    ...High Plains...
    No change from the previous forecast thinking. Weak shortwave
    ridging will reside across the central Rockies/plains northward into
    the northern High Plains. Surface observations and satellite data
    depict a seasonably moist airmass abutted to the Front Range and
    northward into the eastern WY. Heating over the higher terrain and
    along a residual frontal zone will aid in scattered storm
    development this afternoon. The strongest cells will pose some risk
    of hail and gusty winds over the higher terrain before spreading
    onto the plains by late afternoon. Forecast soundings in this
    region show moderately steep mid-level lapse rates, MLCAPE values of
    1000-1500 J/kg, and sufficient vertical shear for transient
    supercell structures. Upscale growth into a linear cluster or two
    may evolve (supported by recent HREF guidance), and this appears
    most probable near the WY/CO/NE border during the early evening. A
    gradual transition from primarily a hail risk to a threat favoring
    severe gusts may occur as outflow becomes more pervasive as storm
    coverage and outflow increases during the evening.

    ...ID/Western MT...
    A mid-level trough over northern NV will move slowly northward
    through tonight into the northern Rockies. Forcing for ascent
    attendant to this upper feature coupled with orographic circulations
    will likely result in scattered storms developing by mid to late
    afternoon. Very steep lapse rates and dry sub-cloud layers will
    promote evaporative cooling and an isolated risk for severe gusts
    (60-70 mph) with the stronger cores and outflow surges.

    ...AR/LA...
    Scattered diurnally driven storms will likely evolve in the vicinity
    of a weakness in the southern U.S. mid-level anticyclone. A very
    moist boundary layer amid moderate buoyancy may result in a few
    stronger water-loaded microbursts capable of 50-65 mph gusts and
    pockets of wind damage.

    $$
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  • From Mike Powell@618:250/1 to All on Sat Aug 9 09:09:14 2025
    ACUS01 KWNS 091249
    SWODY1
    SPC AC 091248

    Day 1 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0748 AM CDT Sat Aug 09 2025

    Valid 091300Z - 101200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE UPPER GREAT LAKES/UPPER MIDWEST...AND EASTERN COLORADO INTO FAR
    WESTERN KANSAS...

    ...SUMMARY...
    Multiple severe/damaging wind swaths should occur today centered on
    parts of Iowa, northwest Illinois, Wisconsin, and the Upper
    Peninsula of Michigan. Large to very large hail will be possible
    across parts of eastern Colorado and vicinity this afternoon and evening.

    ...Upper Great Lakes/Upper Midwest into the Missouri Valley...
    A small but intense bowing cluster has produced numerous severe
    gusts/damage reports (some 75+ mph) in a narrow corridor early this
    morning across south-central NE to western IA. This convection
    should continue east-northeastward across parts of central/northern
    IA through the rest of the morning, with an enhanced southwesterly
    low-level jet providing ample moist inflow. A very unstable airmass
    remains in place ahead of a cold front across this area, with MUCAPE
    around 3000-3500 J/kg. This large reservoir of buoyancy should
    continue to support a severe/damaging wind threat with this cluster
    into parts of central/northern IA for at least the next few hours.
    See Mesoscale Discussion 1911 for more details on the short-term
    severe threat associated with this bowing complex.

    Additional thunderstorms have developed along/near the cold front
    across a broader portion of the Upper Great Lakes and Upper Midwest.
    It still appears probable that multiple swaths of severe/damaging
    winds may occur through the afternoon and evening across parts of
    these regions as the airmass ahead of these thunderstorms gradually destabilizes. With rich low-level moisture already in place, strong
    to extreme instability should once again develop by this afternoon.
    While stronger mid-level flow and related deep-layer shear will tend
    to lag the cold front, they should still be sufficient to support
    organized convection, mainly linear clusters. Some adjustments have
    been made to the Slight Risk to account for the ongoing severe
    thunderstorms in IA, as well as additional activity forecast to
    occur through the afternoon and evening. The potential for
    additional robust convective development tonight across parts of the
    MO Valley remains unclear as a southerly low-level jet strengthens
    once again. Regardless, have maintained severe probabilities across
    southeast NE and vicinity for this possibility.

    ...Central/Southern High Plains...
    A cold front should become nearly stationary by this afternoon
    across the south-central High Plains. A favorable low-level,
    post-frontal regime for severe convection is expected to develop
    across eastern CO by late afternoon. The presence of steep mid-level
    lapse rates, moderate instability, and favorable deep-layer shear
    will likely support scattered supercells capable of large to very
    large hail, localized severe gusts, and possibly a tornado or two
    mainly this afternoon into the evening. Across the southern High
    Plains, high-based convection may again develop across parts of
    eastern NM into the OK/TX Panhandles. This activity could pose a
    isolated threat for severe gusts given a very well-mixed boundary layer.

    ..Gleason/Leitman.. 08/09/2025

    $$
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