• MESO: Mesoscale Discussion 1767

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Sat Sep 18 18:00:12 2021
    This is a multi-part message in MIME format...

    Content-Type: text/plain
    Content-Transfer-Encoding: Quoted-printable

    ACUS11 KWNS 181800
    SPC MCD 181759=20

    Mesoscale Discussion 1767
    NWS Storm Prediction Center Norman OK
    1259 PM CDT Sat Sep 18 2021

    Areas affected...Far northern Arizona into northern Utah

    Concerning...Severe potential...Watch unlikely=20

    Valid 181759Z - 182000Z

    Probability of Watch Issuance...5 percent

    SUMMARY...A couple strong to severe gusts and perhaps an instance of
    large hail may occur with one of the stronger storms. A WW issuance
    is not expected given the relatively brief, localized nature of the
    severe threat.

    DISCUSSION...Current visible satellite imagery depicts some breaks
    in the clouds across portions of the Lower Colorado River Basin,
    promoting modest insolation and associated increasing buoyancy.
    Clusters of ongoing thunderstorms along the AZ/UT border have
    recently supported surface gusts up to 40 kts within the past hour,
    and these storms are poised to move through the aforementioned axis
    of surface heating through the afternoon. The 12Z SLC observed
    sounding showed up to 8 C/km lapse rates within the 700-500 mb
    layer, and with surface temperatures warming through the 70s F (per
    latest METAR observations), widespread 7.5-8.5 surface-500 mb lapse
    rates will result (as already shown by 17Z mesoanalysis). These
    steep lapse rates will contribute to 500 J/kg amid 45 kts of 500 mb
    flow, which may efficiently mix downward within the deep, dry
    boundary layer to support strong to briefly severe wind gusts. A
    brief instance or two of large hail also cannot be ruled out.
    However, the severe threat is expected to remain sparse and brief,
    and a WW issuance appears unlikely.

    ..Squitieri/Hart.. 09/18/2021

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!rq8uOJ1_xPtgjXjnj7tRAhB1rAG1PmORLKbFHQNKB7vS-mxfmQms8GZ8f8zbOA29MCCFwMgm$=
    for graphic product...


    LAT...LON 35581309 38741246 40461186 40921154 40951049 40550999
    39910975 38750973 37560982 37001007 35571126 35581309=20

    Content-Type: text/plain; charset="US-ASCII"
    Content-Disposition: inline
    Content-Transfer-Encoding: 7BIT

    = = =
    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. ------------=_1631988016-91550-1160--

    --- SBBSecho 3.12-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)