• MESO: Mesoscale Discussion 2080

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Sat Dec 31 17:41:48 2022
    ACUS11 KWNS 311741
    SWOMCD
    SPC MCD 311741=20
    CAZ000-312345-

    Mesoscale Discussion 2080
    NWS Storm Prediction Center Norman OK
    1141 AM CST Sat Dec 31 2022

    Areas affected...the higher terrain of the Sierra in northern
    California

    Concerning...Heavy snow=20

    Valid 311741Z - 312345Z

    SUMMARY...Heavy snow is expected to increase in coverage across the
    higher terrain of the Sierra in northern California through the
    afternoon into early evening.

    DISCUSSION...A mid-level trough and accompanying stream of deep
    moisture continues to impinge on the higher terrain of the Sierra in
    northern CA. Strong deep-layer ascent along the windward side of the
    Sierra should lift the deep moisture to a saturated dendritic growth
    zone, favoring heavy snow production. The depth of the rich
    moisture, the presence of weak buoyancy, and combined orographic and
    dynamic lift of moist and buoyant air may foster snowfall rates up
    to the 3-5 inch/hr range, at least on a localized basis and
    particularly above 6000 ft elevations. Latest high-resolution
    guidance consensus suggests that the heavier snowfall rates should
    begin sometime between 18-20Z and become more widespread in the
    higher elevations in the 21-01Z time frame.

    ..Squitieri.. 12/31/2022

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-ahiX_2uRW0esHd5e4IEenRmlGMP7WVTLjasjX0Hpa9F0ijdZX63HDfKoUn9B4a8Eofp6JoE3= 3bjPdDw0rLdhptrUOo$ for graphic product...

    ATTN...WFO...VEF...REV...HNX...STO...

    LAT...LON 39692049 38941999 38391942 38141925 37741893 37481857
    37191831 36961835 36991866 37421925 37921972 38642031
    39062057 39332062 39682064 39692049=20


    =3D =3D =3D
    To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

    --- SBBSecho 3.14-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)
  • From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Mon Sep 4 21:53:21 2023
    ACUS11 KWNS 042153
    SWOMCD
    SPC MCD 042152=20
    NDZ000-SDZ000-042345-

    Mesoscale Discussion 2080
    NWS Storm Prediction Center Norman OK
    0452 PM CDT Mon Sep 04 2023

    Areas affected...northwest and north-central SD...southern and
    central ND

    Concerning...Severe Thunderstorm Watch 666...

    Valid 042152Z - 042345Z

    The severe weather threat for Severe Thunderstorm Watch 666
    continues.

    SUMMARY...Scattered severe gusts are probable across the northeast
    part of severe thunderstorm watch #666 as a band of storms moves
    northeastward. A downstream severe thunderstorm watch is expected
    within the next hour in parts of northern SD and southern ND. Peak
    gusts with the most intense downdrafts are forecast to range 70-90
    mph through 01 UTC (8pm CDT/7pm MDT) over northern SD and southern
    ND.

    DISCUSSION...Radar mosaic late this afternoon shows an intensifying
    band of storms over western SD. Surface analysis ahead of this
    activity indicates temperatures are in the 95-100 deg F range south
    of a southwest-northeast oriented surface trough. The airmass where
    the ongoing storms are located in western SD is adequately moist
    (mid 50s deg F dewpoints) but relatively dry compared to
    south-central ND where dewpoints are in the lower 60s. As a result,
    PW increases from southwest to northeast. This increase in moisture
    will probably result in both storms moving in a more favorable
    environment of buoyancy and moisture for evaporatively cooled
    downdrafts.=20=20

    It appears the most intense phase of the developing squall line will
    commence over the next few hours as storms move into northern SD and
    into southern ND. The negatively tilted mid-level shortwave trough
    over WY will continue to pivot eastward towards the Dakotas this
    evening. The combination of very steep low to mid-level lapse
    rates, a linear storm mode, and appreciable large-scale forcing for
    ascent will favor scattered severe gusts through the evening across
    the Dakotas with the squall line. Peak gusts are forecast to range
    from 70-90 mph.

    ..Smith.. 09/04/2023

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!4M9ErsRzBVTUNsQE_mUb6KubLintIFS3upjOvZyvyNXaljt0e8UaoRIyUZIs7lpzEezvlsqfi= V1QtvciDEsmRHN7tEQ$ for graphic product...

    ATTN...WFO...FGF...ABR...BIS...UNR...

    LAT...LON 44300172 44250220 44340250 45460364 45700370 45950357
    47300105 47409982 47229892 46789830 46129834 45419893
    44300172=20


    =3D =3D =3D
    To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

    --- SBBSecho 3.14-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)