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  • DAY3SVR: Day 3 Convective Outlook

    From COD Weather Processor @1:2320/107 to All on Fri Oct 9 19:31:46 2026
    ACUS03 KWNS 091931
    SWODY3
    SPC AC 091930

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0230 PM CDT Fri Oct 09 2026

    Valid 111200Z - 121200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY ACROSS
    THE MID ATLANTIC AND PORTIONS OF THE LOWER COLORADO VALLEY INTO
    EASTERN GREAT BASIN...

    ...SUMMARY...
    Strong thunderstorms on Sunday may impact parts of the Mid Atlantic,
    and the lower Colorado Valley into eastern Great Basin, accompanied
    by at least some risk for damaging wind gusts and a couple of
    tornadoes.

    ...Discussion...
    Models indicate further consolidation of troughing within initially
    separate branches of the westerlies, with slow progression inland of
    the Pacific coast Sunday through Sunday night. Within southerly
    flow ahead of the evolving large-scale trough axis, remnants of
    Tropical Storm Rachel are forecast to rapidly advect from the
    southeastern California Sonoran Desert toward the western slopes of
    the Wasatch through the day Sunday. As downstream mid/upper ridging
    builds through the southeastern Great Plains and middle/lower
    Mississippi Valley, it appears that an upper trough and remnant
    mid-level cyclonic circulation will be forced east-northeastward
    across the Appalachians through Mid Atlantic. Associated forcing
    for ascent may support modest secondary surface cyclogenesis to the
    lee of the Blue Ridge, southeast of the weakening remnants of Isaias
    across the Cumberland/Allegheny Plateau vicinity, and in the wake of
    weakening surface ridging shifting offshore of the Atlantic
    Seaboard.

    Spread among the models remains substantive concerning the shorter
    wavelength perturbations, but a couple areas with at least some
    potential for severe thunderstorm development are evident.

    ...Mid Atlantic...
    Given the seasonably high boundary-layer moisture content advecting
    northward toward the Mid Atlantic in advance of the developing
    surface low, there appears potential for boundary-layer
    destabilization coincident with strengthening low-level and
    deep-layer shear. Models suggest that a developing mid-level dry
    slot could provide a focus for the most substantive boundary-layer destabilization by late Sunday afternoon across parts of eastern
    Virginia into eastern North Carolina, where insolation prior to the
    onset of mid-level ascent/cooling may support a period of vigorous
    thunderstorm development. It appears that this could include
    supercell structures within an evolving broken line of storms, which
    may pose a risk for a couple of tornadoes and/or locally damaging
    wind gusts.

    ...Lower Colorado Valley into eastern Great Basin...
    Boundary-layer destabilization and convective potential is more
    unclear along the forecast track of Rachel for Sunday. However,
    given the development of sufficient instability, the remnant strong south-southwesterly wind fields could provide support for organized
    convection, including supercell structures, posing at least a risk
    for damaging wind gusts.

    ..Kerr.. 10/09/2026

    $$
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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sat Oct 10 07:23:28 2026
    ACUS03 KWNS 100723
    SWODY3
    SPC AC 100721

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0221 AM CDT Sat Oct 10 2026

    Valid 121200Z - 131200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    No severe weather is expected Monday through Monday night.

    ...Synopsis...

    A midlevel low initially over the Columbia Basin is forecast to
    progress south toward the Sierra Nevada, while an upper-level jet
    streak develops from the lower-CO Valley into the Upper Midwest.
    Ahead of the latter feature, a low-amplitude short-wave trough is
    projected to move from the northern High Plains into the Upper
    Midwest, embedded within a belt of 40-50 kt midlevel flow. In the
    low levels, an area of low pressure loosely related to the
    short-wave trough is expected to develop from the mid-MO Valley into
    the Upper Midwest along a stationary front. A cold front will trail
    southwest from that feature, linking with a secondary cyclone over
    the central High Plains.

    ...Upper Midwest/Upper Great Lakes...

    A plume of relatively steep midlevel lapse rates of around 7 C/km
    will overlie the northern extension of a moistening boundary layer,
    supporting a corridor of moderate instability by afternoon to the
    south of the surface low and associated front described in the
    synopsis. Capping at the base of the lapse-rate plume/EML is likely
    to inhibit surface-based storm development in the warm sector.
    However, the 00Z models suggest that a cluster of elevated
    thunderstorms may persist Monday afternoon into night to the
    immediate north of the warm sector within a zone of forcing for
    ascent preceding the short-wave trough. While a few strong storms
    capable of small hail appear possible, marginal parcel buoyancy and
    only modest cloud-bearing shear are expected to limit the threat for
    severe weather.

    ..Mead.. 10/10/2026

    $$
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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sat Oct 10 19:02:28 2026
    ACUS03 KWNS 101902
    SWODY3
    SPC AC 101901

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0201 PM CDT Sat Oct 10 2026

    Valid 121200Z - 131200Z

    ...NO SEVERE THUNDERSTORM AREAS FORECAST...

    ...SUMMARY...
    No severe weather is expected Monday through Monday night.

    ...Discussion...

    An upper low and attendant shortwave trough will pivot across
    portions of the Southwest and Great Basin on Monday. An enhanced
    midlevel jet streak associated with this system and lingering
    boundary layer moisture will support showers and isolated
    thunderstorm activity. Instability will remain weak, limiting severe thunderstorm potential.

    Further northeast, a weak midlevel shortwave impulse will migrate
    northeast from the central High Plains toward the Mid/Upper MS
    Valley, flattening the central U.S. upper ridge. A weak surface low
    over the Upper MS Valley will shift east through the Great Lakes,
    and a trailing cold front will sweep southeast across the Upper
    Midwest to the Mid-MO Valley. Boundary layer moisture will remain
    modest, but cool temperatures aloft will support modest instability
    atop midlevel capping across parts of central/southern WI. A few
    elevated thunderstorms are possible within this modestly sheared and
    weakly unstable environment ahead of the cold front. Small hail
    could occur with the strongest storms. However, severe potential
    appears too limited to include low probabilities at this time.

    Additional thunderstorms are possible across portions of
    south/southeast TX within a low-level warm advection regime on the
    western periphery of surface high pressure centered over the central
    Gulf coast vicinity. Isolated thunderstorms may also occur as a cold
    front develops south across southern FL and the Keys during the
    afternoon.

    ..Leitman.. 10/10/2026

    $$
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    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sun Oct 11 07:02:36 2026
    ACUS03 KWNS 110702
    SWODY3
    SPC AC 110701

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0201 AM CDT Sun Oct 11 2026

    Valid 131200Z - 141200Z

    ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
    CENTRAL AND SOUTHERN HIGH PLAINS...

    ...SUMMARY...
    Widely scattered severe storms appear possible over portions of the
    central and southern High Plains Tuesday afternoon into night. More
    isolated severe weather may occur into the mid Mississippi Valley,
    and in parts of the lower Great Lakes.

    ...Synopsis...

    A midlevel low will slowly progress through the Great Basin with a
    downstream belt of enhanced, mid/upper-level flow extending from the
    southern Rockies into the Great Lakes. Within that airstream, a
    short-wave trough will progress from the Great Lakes into the
    Northeast, while a more subtle disturbance advances from the central
    and southern High Plains into the Upper Midwest. At the surface, an
    area of low pressure associated with the former disturbance
    mentioned above is expected to develop from lower MI through the
    northern Mid-Atlantic into New England with a boundary trailing that
    feature from the southern Great Lakes into the central High Plains,
    where it will link with a deepening lee cyclone over southeast CO.


    ...Central and Southern Plains into the Mid-Mississippi Valley...

    While midlevel lapse rates are not forecast to be particularly
    steep, daytime heating combined with boundary-layer dewpoints in the
    mid 60s to lower 70s is expected to contribute to a moderately
    unstable warm sector by afternoon. The specific details regarding
    convective evolution remain uncertain; however, forcing for ascent
    associated with the midlevel disturbance and convergence in the
    vicinity of the synoptic front, dryline, and lee cyclone are likely
    to aid in diurnally enhanced thunderstorm development. Highest
    confidence in that occurrence remains over portions of southwest KS
    into the OK and TX Panhandles, where the low-level mass response to
    the deepening CO low will be the greatest from late afternoon into
    evening. Vertical shear will be sufficiently strong to support
    supercells capable of mainly large hail initially. Tornado potential
    may increase during the evening with any ongoing supercells as the
    low-level jet strengthens. Upscale growth into one or multiple storm
    complexes appears possible, at which point, the threat for damaging
    winds would correspondingly increase.

    An areal expansion in level-2/Slight Risk probabilities may be
    required in later outlooks once finer-scale details become more
    clear.


    ...Lower Great Lakes...

    Showers and thunderstorms may be ongoing Monday morning within a
    zone of low-level warm advection and moisture transport preceding
    the surface low and short-wave trough. Clouds and precipitation may
    linger into afternoon, limiting the destabilization in those areas.
    However, where stronger heating can occur, the presence of
    boundary-layer dewpoints in the 60s will support at least a
    marginally unstable environment by afternoon. Both low-level and
    deep-layer shear will be relatively strong, and on the condition
    that surface-based storms develop and are sustained, the threat for
    locally damaging winds and perhaps a tornado or two would exist.

    ..Mead.. 10/11/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Sun Oct 11 19:10:30 2026
    ACUS03 KWNS 111910
    SWODY3
    SPC AC 111909

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0209 PM CDT Sun Oct 11 2026

    Valid 131200Z - 141200Z

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

    ...SUMMARY...
    Widely scattered severe storms appear possible over portions of the
    central and southern High Plains Tuesday afternoon into night. More
    isolated severe weather may occur into the mid Mississippi Valley,
    and in parts of the Lower Great Lakes.

    ...Central/Southern Plains to Mid-MS Valley...

    Enhanced mid/upper southwesterly flow will reside across the region
    on Tuesday in advance of an eastward-propagating upper low over the
    Great Basin to central Rockies vicinity. At the surface, weak lee
    low development is forecast across southeast CO/southwest KS, with
    surface troughing extending southward across the southern High
    Plains. Meanwhile, a surface front will extend from the High Plains
    low east/northeast across northern KS toward northern IL during the
    evening. Southerly low-level flow and a strengthening low-level jet
    will support mid 60s to near 70 F dewpoints across the warm sector
    from portions of western TX into OK/KS and the Mid-MS Valley. While
    midlevel lapse rates are not forecast to be particularly strong,
    rich boundary layer moisture will foster 1000-2000 J/kg MLCAPE.

    Where stronger heating occurs in closer proximity to the surface
    trough and triple point from northwest TX into central KS,
    supercells will be possible amid vertically veering wind profiles.
    Damaging winds and a tornado or two appear possible within this zone
    of better instability and shear. Convection is likely to increase
    along the breadth of the surface front into the Lower MO/Mid-MS
    Valley as warm advection increases during the evening and overnight
    hours. This convection may tend to be elevated within isentropic
    ascent atop the surface front, further supported by
    boundary-parallel wind profiles. Midlevel temperatures are forecast
    to be cooler, and MUCAPE could approach 1000-1500 J/kg. Marginal
    hail and gusty winds may accompany this activity into the nighttime
    hours.

    ...Lower Great Lakes...

    Showers and thunderstorms are likely to be ongoing Tuesday morning
    ahead of an approaching midlevel shortwave impulse over the Great
    Lakes. Deep-layer westerlies will increase through the day as this
    disturbance approaches, resulting in a moderately to strongly
    sheared environment. If sufficient heating can occur, surface
    dewpoints near 60 F will aid in modest destabilization, resulting in
    a conditionally favorable environment for localized strong wind
    gusts and perhaps a tornado.

    ..Leitman.. 10/11/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Mon Oct 12 07:23:02 2026
    ACUS03 KWNS 120722
    SWODY3
    SPC AC 120721

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0221 AM CDT Mon Oct 12 2026

    Valid 141200Z - 151200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF THE CENTRAL AND SOUTHERN PLAINS INTO THE OZARK PLATEAU...

    ...SUMMARY...
    Isolated severe thunderstorms are possible across portions of the
    central and southern Plains into the Ozark Plateau Wednesday
    afternoon and evening.

    ...Synopsis...

    An upper low centered over UT and AZ Wednesday morning is forecast
    to advance into CO while an embedded vorticity maximum pivots
    through the basal portion of the low into the southern Rockies and
    adjacent High Plains by Wednesday evening. Modest height falls and strengthening midlevel flow will precede that disturbance, spreading
    into the southern and central High Plains Wednesday afternoon and
    evening. At the surface, a cold front will settle south through the Mid-Atlantic and OH Valley. The position of the front over the
    central and southern Plains will likely be modulated by ongoing
    showers and thunderstorms Wednesday morning.


    ...Central and Southern Plains into the Ozark Plateau...

    As mentioned above, considerable shower and thunderstorm activity is
    expected to be ongoing at 12z Wednesday along and south of the
    synoptic front. The presence of a seasonably moist and minimally
    capped warm sector will likely allow thunderstorms to continue
    through the forecast period, especially as forcing for ascent
    increases Wednesday afternoon into evening. Corridors of moderate
    instability appear possible by afternoon to the south of any more
    persistent clouds and precipitation with associated outflow
    boundaries potentially serving as foci for strong to potentially
    severe storm development during the afternoon and evening.

    Latest model guidance suggests that the strongest vertical shear may
    reside across a convectively overturned air mass closer to the
    synoptic front with decreasing shear magnitudes with southward
    extent where greater instability is more probable. Given these
    potential issues/uncertainties, only level-1/Marginal Risk
    probabilities will be included in this forecast.


    ...Ohio Valley into the Mid-Atlantic...

    Convective evolution on this segment of the cold front remains more
    uncertain due to the absence of any appreciable forcing mechanisms
    in 00Z model data. Nonetheless, a moist boundary layer will reside
    to the south of the front, supporting pockets of moderate
    instability in areas that experience stronger daytime heating. A
    strong storm or two appears possible along the front during the
    afternoon and evening hours with a risk for locally gusty winds. The
    area will be reevaluated in subsequent outlooks for the possible
    inclusion of severe weather probabilities.

    ..Mead.. 10/12/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Mon Oct 12 19:06:16 2026
    ACUS03 KWNS 121905
    SWODY3
    SPC AC 121904

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0204 PM CDT Mon Oct 12 2026

    Valid 141200Z - 151200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
    THE SOUTHERN PLAINS AND OZARKS...

    ...SUMMARY...
    Isolated severe thunderstorms are possible across portions of the
    southern Plains into the Ozark Plateau Wednesday afternoon and
    evening.

    ...Southern Plains to the Ozark Plateau...

    Enhanced southwesterly deep-layer flow will persist across the
    region as an upper low develops east/northeast from the Southwest to
    the central High Plains on Wednesday. Surface high pressure is
    forecast to build eastward from the northern Plains to the Great
    Lakes as a surface cold front sags southward from the Ohio Valley
    into the southern Plains. Ahead of this boundary, rich boundary
    layer moisture will be in place, characterized by surface dewpoint
    in the mid 60s to mid 70s F. Showers and thunderstorms will likely
    be ongoing Wednesday morning in the vicinity of the surface front,
    and some downstream cloudiness will likely limit stronger heating
    across portions of the warm sector. Nevertheless, pockets of
    moderate instability are expected to develop from west TX toward the
    Ozark Plateau. As vertical shear and large-scale ascent increase
    during the afternoon, isolated strong to severe storms may develop
    within these pockets of stronger heating and destabilization as the
    surface front sags southward.

    ...Ohio Valley...

    A moist airmass will be in place ahead of a southward-sagging cold
    front. Stronger vertical shear and any appreciable large-scale
    forcing will remain displaced from the warm sector across the Lower
    OH Valley. Modest destabilization will support widely scattered
    thunderstorm develop from the Mid-South into southern OH and parts
    of KY through early evening. However, severe potential is more
    uncertain, compared to portions of the Plains/Ozarks, with northeast
    extent along the surface boundary given poor lapse rates, weaker
    vertical shear and nebulous large-scale ascent.

    ..Leitman.. 10/12/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Tue Oct 13 08:03:22 2026
    ACUS03 KWNS 130709
    SWODY3
    SPC AC 130708

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0208 AM CDT Tue Oct 13 2026

    Valid 151200Z - 161200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
    THE MID-MISSISSIPPI AND OHIO VALLEYS...

    ...SUMMARY...
    Isolated severe storms appear possible over portions of the mid-
    Mississippi and Ohio Valleys Thursday afternoon through night.

    ...Synopsis...

    A short-wave trough over SK/MB Thursday morning is forecast to
    undergo considerable amplification while translating into the Great
    Lakes late Thursday night/early Friday. Ahead of that feature, an
    upper low will weaken into an increasingly sheared open wave while
    accelerating from the central High Plains into the Midwest. At the
    surface, an area of low pressure is expected to develop along a poleward-advancing warm front from central or eastern KS through the
    mid-MS and OH Valleys to the lower Great Lakes. Meanwhile a trailing
    cold front will surge south through much of the southern Plains and
    into the lower-MS Valley.


    ...Mid-Mississippi and Ohio Valleys...

    Showers and thunderstorms may be ongoing at 12Z Thursday from
    portions of the central Plains into the mid-MS Valley within a zone
    of warm-air and moisture advection preceding the surface low. A
    subset of the early-day storms may persist through the day with
    associated cloud cover limiting daytime heating and resultant air
    mass destabilization in those areas. Where cloud breaks can occur,
    stronger diabatic heating coupled with boundary-layer dewpoints in
    the low to mid 70s may contribute to a corridor of moderate
    instability by afternoon, which would become a preferred zone of
    diurnally enhanced thunderstorm development.

    Both vertical shear and forcing for ascent are forecast to steadily
    strengthen from Thursday afternoon through night, leading to the
    potential for a fast-moving complex of storms to traverse the region
    with an associated risk for locally damaging wind gusts.

    ..Mead.. 10/13/2026

    $$
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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Tue Oct 13 19:31:44 2026
    ACUS03 KWNS 131931
    SWODY3
    SPC AC 131930

    Day 3 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0230 PM CDT Tue Oct 13 2026

    Valid 151200Z - 161200Z

    ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
    OF THE MID MISSISSIPPI VALLEY AND MIDWEST...

    ...SUMMARY...
    Isolated severe storms are possible over portions of the mid-
    Mississippi Valley and Midwest Thursday afternoon and evening.

    ...Mid MS Valley/Midwest...
    The upper low ejecting over the central Plains is forecast to weaken
    to a positive-tilt open wave as it continues eastward and merges
    with a northern stream trough from southern Canada late Thursday.
    The lee low over KS will continue eastward and strengthen as a
    diffuse warm front lifts northward across the Mid MS and lower OH
    Valleys. A cold front will trail the low, sweeping south and east
    from the MO valley into the southern Plains.

    Scattered to numerous thunderstorms are expected to be ongoing early
    Thursday ahead of the low within a zone of low-level warm air
    advection from the central Plains into the mid-MS Valley. A narrow
    plume of upper 60s to low 70s F dewpoints will be advected
    northeastward ahead of this activity across eastern IA/MO into
    western IL. Modest clearing/heating of the air mass should support
    weak destabilization with MLCAPE of 500-750 J/kg. This will allow
    for intensification of the storms/new development through the
    afternoon. Increasing ascent/vertical shear (EBWD 45-60 kt) will
    support the potential for one or more organized clusters of storms
    capable of damaging wind gusts through Thursday evening.

    Farther southwest across OK/TX, a broken band of showers and storms
    may still be ongoing ahead of the surging cold front Thursday
    morning. Low-level flow should quickly veer as the front accelerates
    favoring undercutting. Poor lapse rates, multiple rounds of prior
    precipitation and rapidly decreasing surface moisture suggest only
    weak buoyancy will be present. This should limit severe potential,
    though a stray severe gust cannot be completely ruled out.

    ..Lyons.. 10/13/2026

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