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  • DAY48SVR: Nws Storm Prediction Center Norman Ok

    From COD Weather Processor @1:2320/107 to All on Mon Oct 5 08:59:16 2026
    ACUS48 KWNS 050859
    SWOD48
    SPC AC 050857

    Day 4-8 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0357 AM CDT Mon Oct 05 2026

    Valid 081200Z - 131200Z

    ...DISCUSSION...
    Little severe weather threat is evident from Thur/D4 through Fri/D5,
    as a broad upper trough over the Great Lakes and Northeast maintain
    cool conditions, with high pressure over much of the eastern states
    preventing moisture return.

    For late Sat/D6 into Sun/D7, conditional severe potential may
    develop along the northern Gulf Coast, depending on the evolution of
    a tropical disturbance currently over the southwest Gulf of America.
    NHC currently denotes a 50% chance of cyclone development. A weak
    midlevel trough is also forecast to develop over TX, and move across
    the Gulf Coast states during the same time. The combination of
    increasing moisture and shear could result in an area of tornado
    potential. Any such event is highly conditional on cyclone
    formation, and potential will continue to be monitored.

    From Sun/D7 and beyond, models suggest a western trough may develop,
    though model spread is high.

    ..Jewell.. 10/05/2026

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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 6 08:14:24 2026
    ACUS48 KWNS 060814
    SWOD48
    SPC AC 060812

    Day 4-8 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0312 AM CDT Tue Oct 06 2026

    Valid 091200Z - 141200Z

    ...DISCUSSION...
    A surface high will move from the OH Valley into the Northeast on
    Fri/D4 as an upper trough lifts out of the region and temporary
    upper ridging occurs. A stationary boundary is still forecast to be
    along the northern Gulf Coast at this time, and a weak midlevel wave
    will begin to form over TX. Meanwhile, a potential tropical cyclone
    may develop toward the central Gulf of America.

    Low-level winds will begin to veer to a southeasterly direction
    along the Gulf Coast late Fri/D4 into Sat/D5, as the potential
    tropical cyclone evolves. NHC currently gives a high probability of
    this occurring. As such, an influx of rich moisture will develop out
    of the south, with a substantial rain shield and embedded
    thunderstorms likely along the northern Gulf Coast beginning Fri/D4
    night. Initially, surface temperatures over land will remain cool
    due to precipitation and initial modification of the surface ridge
    air mass.

    At this time, it appears Sat/D5 is the most likely time for the more substantial low-level warming to occur, with tropical yet
    sufficiently unstable profiles. Of particular note is how the
    developing shortwave trough over TX interacts with the tropical low.
    Some models indicate 40-45 kt midlevel winds, which would complement
    the strong low-level shear and favor low-topped supercells with
    tornado potential. The greatest threat area should be along the
    coastal counties given expected poor low-level lapse rates farther
    inland. Initial elevated convection may give way to an east-west
    zone of supercells as the coastal baroclinic zone moves inland. Some
    additional threat into Sun/D6 may exist as well.

    For the period Mon/D7 into Tue/D8, models are now developing an
    amplified upper trough over the western CONUS. Low-level moistening
    will be most prominent later in the period, and could eventually
    result in a zone of strong to severe storm potential, however,
    predictability is quite low at this time.

    ..Jewell.. 10/06/2026

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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 6 08:31:54 2026
    ACUS48 KWNS 060831
    SWOD48
    SPC AC 060829

    Day 4-8 Convective Outlook RESENT 1
    NWS Storm Prediction Center Norman OK
    0329 AM CDT Tue Oct 06 2026

    Valid 091200Z - 141200Z

    ...DISCUSSION...
    A surface high will move from the OH Valley into the Northeast on
    Fri/D4 as an upper trough lifts out of the region and temporary
    upper ridging occurs. A stationary boundary is still forecast to be
    along the northern Gulf Coast at this time, and a weak midlevel wave
    will begin to form over TX. Meanwhile, a potential tropical cyclone
    may develop toward the central Gulf of America.

    Low-level winds will begin to veer to a southeasterly direction
    along the Gulf Coast late Fri/D4 into Sat/D5, as the potential
    tropical cyclone evolves. NHC currently gives a high probability of
    this occurring. As such, an influx of rich moisture will develop out
    of the south, with a substantial rain shield and embedded
    thunderstorms likely along the northern Gulf Coast beginning Fri/D4
    night. Initially, surface temperatures over land will remain cool
    due to precipitation and initial modification of the surface ridge
    air mass.

    At this time, it appears Sat/D5 is the most likely time for the more substantial low-level warming to occur, with tropical yet
    sufficiently unstable profiles. Of particular note is how the
    developing shortwave trough over TX interacts with the tropical low.
    Some models indicate 40-45 kt midlevel winds, which would complement
    the strong low-level shear and favor low-topped supercells with
    tornado potential. The greatest threat area should be along the
    coastal counties given expected poor low-level lapse rates farther
    inland. Initial elevated convection may give way to an east-west
    zone of supercells as the coastal baroclinic zone moves inland. Some
    additional threat into Sun/D6 may exist as well.

    For the period Mon/D7 into Tue/D8, models are now developing an
    amplified upper trough over the western CONUS. Low-level moistening
    will be most prominent later in the period, and could eventually
    result in a zone of strong to severe storm potential, however,
    predictability is quite low at this time.

    ..Jewell.. 10/06/2026

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Wed Oct 7 08:28:04 2026
    ACUS48 KWNS 070827
    SWOD48
    SPC AC 070826

    Day 4-8 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0326 AM CDT Wed Oct 07 2026

    Valid 101200Z - 151200Z

    ...DISCUSSION...
    For Sat/D4, the latest NHC guidance (as of this writing) has brought
    the center track of the developing hurricane farther east toward
    southern AL and the western FL Panhandle, and thus the Slight Risk
    for tornado potential has been shunted east. Further, given the
    likelihood of a stronger cyclone and faster forward motion, the
    Slight Risk has also been expanded farther north/inland, as it
    appears the mid 70s F dewpoints may expand across much of southern
    AL. The strong low-level shear east of the center, and increasing
    midlevel winds (as a shortwave trough deepens over the Lower MS
    Valley) should support a few supercells with tornado potential. It
    should be noted that the Slight Risk area may shift in subsequent
    outlooks if the center track shifts.

    For Sun/D5, the shortwave trough and remnants of the tropical
    cyclone will generally move northeastward toward the Appalachians
    and toward the Carolinas and southern Mid Atlantic. It is possible
    that the upper system outruns the unstable warm sector, but at least
    a low end chance of severe is not out of the question.

    For the remainder of the period, there may be a chance of severe
    storms over parts of the Southern Plains into Wed/D8 as a developing
    western trough eventually moves across the Rockies, and low-level
    moisture returns in earnest. However, the evolution of this trough
    and date of wave ejection is low predictability.

    ..Jewell.. 10/07/2026

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Thu Oct 8 08:23:36 2026
    ACUS48 KWNS 080823
    SWOD48
    SPC AC 080821

    Day 4-8 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0321 AM CDT Thu Oct 08 2026

    Valid 111200Z - 161200Z

    ...DISCUSSION...
    On Sun/D4, a shortwave trough and surface low (previously associated
    with the tropical cyclone) will move east across the TN/OH Valleys,
    and toward the Mid Atlantic Sunday night. A warm front and northward
    surge of moisture will occur from GA/Carolinas into VA/DelMarVa,
    resulting in at least a few hundred J/kg MLCAPE. Substantial rain
    and thunderstorms are likely to exist over the region, and therefore
    boundary layer warming/destabilization is in question. Most models
    show little if any daytime heating. As such, predictability is low
    at this time, but at least low severe probabilities could be added
    in later outlooks as the scenario evolves.

    To the west, a shortwave trough with tropical remnants will affect
    southern CA and AZ, with strong southwest winds aloft. Substantial
    model differences exist regarding destabilization due to increasing
    clouds and rain, though some severe wind and even hail potential
    cannot be ruled out where instability is locally higher. This area
    too may see at least low severe probabilities in later outlooks as predictability increases.

    For the remainder of the period through Thu/D8, a potential western
    trough ejection may occur into the Plains, with the strongest
    instability on or after Wed/D7 as moisture return becomes more
    established with upper 60s F dewpoints possible from TX into OK and
    KS. As such, this area will also be monitored as the event nears,
    and as trough timing becomes more predictable.

    ..Jewell.. 10/08/2026

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    --- scorpsmtpd
    * Origin: capitolcityonline.net * KY, USA (1:2320/107)
  • From COD Weather Processor @1:2320/107 to All on Fri Oct 9 18:40:14 2026
    ACUS48 KWNS 090905
    SWOD48
    SPC AC 090903

    Day 4-8 Convective Outlook
    NWS Storm Prediction Center Norman OK
    0403 AM CDT Fri Oct 09 2026

    Valid 121200Z - 171200Z

    ...DISCUSSION...
    There is reasonably good agreement in 00Z deterministic and ensemble
    guidance that a mid/upper-level low centered over the Sierra Nevada
    or Great Basin on Day 4/Monday will evolve into an open wave while
    progressing into the Great Plains on Day 6/Wednesday. Thereafter,
    model spread increases in the evolution of the large-scale pattern.

    ...Day 4/Monday...

    Some severe weather threat could materialize during the afternoon
    along a surface boundary over the Upper Midwest where at least
    modest instability will coincide with sufficiently strong deep-layer
    shear to support organized storm modes. However, low-amplitude
    ridging downstream from the western U.S. trough along with
    uncertainty in the extent of air mass destabilization renders the
    threat too questionable to include a 15% area.


    ...Day 5/Tuesday...

    Increasing height falls and midlevel flow will overspread the
    central and southern High Plains, which in turn will induce a
    deepening lee cyclone, likely over southeast CO. At the surface, a
    front is expected to stretch from the low through the OH Valley into
    the Mid-Atlantic with a dryline trailing south from the cyclone into
    eastern NM or western TX. Isolated strong to severe storms appear
    possible along the length of the front from the Mid-Atlantic into
    the central and southern Plains. Organized severe storm potential
    appears most probable over the central and southern High Plains
    Tuesday afternoon into evening in the vicinity of the lee cyclone
    and strengthening low-level jet, where the strongest forcing for
    ascent and vertical shear will coincide.


    ...Day 6/Wednesday...

    As mentioned above, there is overall model agreement that a
    short-wave trough and a strengthening deep-layer wind field will
    advance into the Great Plains at this time. However, there are
    slight timing and latitudinal differences in the track of the
    midlevel system and the associated surface low. Despite these
    differences, it does appear that a broad, moist, and unstable warm
    sector will exist. As such, organized severe storms appear possible
    with the highest confidence in occurrence over portions of eastern
    KS into MO where guidance currently indicates the most favorable
    overlap of instability and vertical shear. The currently delineated
    area may move slightly and/or expand in the coming days as forecast
    confidence increases.


    ...Days 7 and 8/Thursday and Friday...

    Some severe weather threat could develop over the Great Lakes and OH
    Valley on Thursday in association with the mid-level trough
    discussed in the previous sections. However, confidence in organized
    severe storm potential is currently too low given the model
    variability in the specific details of the trough and associated
    frontal system.

    ..Mead.. 10/09/2026

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