• MESO: Mesoscale Discussion 1542

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Thursday, July 21, 2022 22:38:14
    ACUS11 KWNS 212238
    SWOMCD
    SPC MCD 212237=20
    ALZ000-MSZ000-ARZ000-LAZ000-220000-

    Mesoscale Discussion 1542
    NWS Storm Prediction Center Norman OK
    0537 PM CDT Thu Jul 21 2022

    Areas affected...southern Arkansas....northern Louisiana...central
    Mississippi

    Concerning...Severe Thunderstorm Watch 481...482...

    Valid 212237Z - 220000Z

    The severe weather threat for Severe Thunderstorm Watch 481, 482
    continues.

    SUMMARY...Potential still exists for strong thunderstorm development
    with gusty winds to spread into portions of north central
    Mississippi through 8-10 PM CDT.

    DISCUSSION...A weak low-level convergence zone extending from parts
    of northeastern Oklahoma into southeastern Arkansas has become the
    focus for increasingly widespread intense thunderstorm development
    the past couple of hours, in the presence of steep lapse rates and
    large CAPE. Beneath the enlarging, cold cloud tops, consolidating
    outflow has been spreading radially outward from an area centered
    roughly west-southwest of Hot Springs, AR.

    Deep-layer mean flow is weakly sheared and not particularly
    conducive to organized convective development, but there is a north-northwesterly component around 10 kt across the Ozark Plateau
    through the lower Mississippi Valley. This favors the southeastward
    advancing segment of the convective outflow for most likely renewed thunderstorm development as it gradually spreads out from initiating convection, particularly with the more moist and potentially
    unstable environment centered over the lower Mississippi Valley. So
    the High Resolution Rapid Refresh depiction of stronger convection
    developing along the surface boundary through southeastern Arkansas
    into north central Mississippi through 01-03Z seems plausible, but
    it is not certain.

    ..Kerr.. 07/21/2022

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!9EalFkHUDb7HCvpY9Q5OdCbPbcV0s35WAwFhcWGW6S7A6R0wIBtgN0_EjT-7FVel1eDw1RL3L= 6jy8NXNNE7fG93HvGk$ for graphic product...

    ATTN...WFO...BMX...MEG...JAN...LZK...SHV...

    LAT...LON 34279318 34079194 34089121 34279004 33428826 32628852
    32418980 32469099 33149277 33619353 34279318=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 Friday, July 14, 2023 16:25:11
    ACUS11 KWNS 141625
    SWOMCD
    SPC MCD 141624=20
    MOZ000-KSZ000-141830-

    Mesoscale Discussion 1542
    NWS Storm Prediction Center Norman OK
    1124 AM CDT Fri Jul 14 2023

    Areas affected...Much of KS into far western MO

    Concerning...Severe potential...Severe Thunderstorm Watch likely=20

    Valid 141624Z - 141830Z

    Probability of Watch Issuance...95 percent

    SUMMARY...The threat for scattered to numerous severe wind gusts,
    with some 75+ mph, is expected to increase this afternoon. Some
    threat for large hail will also exist. Severe Thunderstorm Watch
    issuance will be needed as thunderstorms spread southeastward from
    Nebraska into Kansas.

    DISCUSSION...A small cluster/supercell in south-central NE is
    beginning to show signs of upscale growth and a developing
    rear-inflow jet based on recent radar imagery from KUEX. Indeed,
    measured severe wind gusts up to 64 mph have recently been recorded
    with this cluster. An increasing threat for severe/damaging winds is
    expected as this activity spreads southeastward this afternoon
    across much of KS. A moderately to strongly unstable airmass and
    steep mid-level lapse rates are present over western/central KS,
    along and south of a convectively reinforced front (reference 12Z
    DDC sounding). The airmass across eastern KS into western MO is less
    unstable at the moment. But, continued robust diurnal heating of a
    very moist low-level airmass across this region will act to increase
    MLCAPE to around 2500-3000+ J/kg over the next few hours.

    KS is on the southern periphery of stronger northwesterly mid-level
    flow. Still, enough deep-layer shear should be present to support
    continued convective organization, with latest mesoanalysis
    estimates showing 30-40 kt of effective bulk shear across KS. In
    addition to the intense cluster/supercell in south-central NE, a
    separate area of convection has developed along the surface boundary
    across northeast KS. There is some potential for this activity to
    also grow upscale into a severe wind producing MCS and impact
    northeastern KS and parts of western MO. Otherwise, the primary
    severe wind threat should remain focused with the cluster moving
    southeastward out of NE and into central/eastern KS this afternoon.

    A large reservoir of available buoyancy, steep mid-level lapse
    rates, and an organized/intense bow shown in most
    convection-allowing guidance all suggest a threat for significant severe/damaging gusts of 75-80+ mph across this region this
    afternoon. Large hail will also remain a risk with any supercell
    that can be sustained within or on the southwest flank of the
    developing bow. Based on its current track, Severe Thunderstorm
    Watch issuance will be needed soon for much of central/eastern KS
    and vicinity.

    ..Gleason/Bunting.. 07/14/2023

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!7fv0jZKbsBxFCM2dAmmGr4VCi0HS-iGI6z6TObULR7lcnoCYwCsNVFthDQC7OXCEHLs7zl1rv= Jyly7au0cLC9QuzvZs$ for graphic product...

    ATTN...WFO...EAX...TOP...ICT...DDC...

    LAT...LON 38960007 37849968 37059864 37309623 38059512 38659396
    39599374 39939495 39909751 39419777 39159795 39039915
    38960007=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)