• MESO: Mesoscale Discussion 0905

    From COD Weather Processor@1:2320/105 to wx-storm@lists.illinois.edu on Tue May 20 18:37:16 2025
    ACUS11 KWNS 201837
    SWOMCD
    SPC MCD 201836=20
    INZ000-ILZ000-202030-

    Mesoscale Discussion 0905
    NWS Storm Prediction Center Norman OK
    0136 PM CDT Tue May 20 2025

    Areas affected...much of central Illinois and adjacent west central
    Indiana

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

    Valid 201836Z - 202030Z

    Probability of Watch Issuance...95 percent

    SUMMARY...Thunderstorm development will continue to gradually
    intensify through 2-4 PM CDT, posing increasing risk for severe
    weather.

    DISCUSSION...Low-level convergence and boundary-layer
    destabilization is becoming maximized across much of central
    Illinois, within the warm sector to the southeast of the primary
    surface low center now over southeastern Iowa. This will continue
    to be aided by mid-level cooling and forcing for ascent associated
    with a still well-defined cyclonic vorticity center to the
    west-northwest of Quincy IL, which is forecast to continue a slow
    northeastward and eastward migration across the Midwest through late afternoon.=20

    Thermodynamic profiles, particularly centered across and southeast
    of the Springfield area, appear characterized by rather steep lower/mid-tropospheric lapse rates, with mixed-layer CAPE increasing
    in excess of 1000 J/kg. As residual inhibition associated with the
    remnants of elevated mixed-layer air continues to erode, the
    environment is becoming supportive of organized convection
    near/beneath the exit region of a strong mid/upper jet. This may
    include discrete a few discrete supercells and perhaps an organizing
    cluster with potential to produce severe hail and damaging wind
    gusts.=20=20

    Modest clockwise-curved low-level hodographs may also support a risk
    for tornadoes, particularly with the more discrete storms.

    ..Kerr/Hart.. 05/20/2025

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!8pom7FtIvP1kDCtmfrCwFlyJvaT0FdMXo4iUnmaRhBcT5ezZ-3LqrRETvzoPWxjbRg6C5Wqg2= PKZ_zbRoxasQ5eIIqk$ for graphic product...

    ATTN...WFO...IND...LOT...ILX...LSX...DVN...

    LAT...LON 41188923 40728835 38858721 38988952 39868947 40358973
    41188923=20

    MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH


    =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 3.20-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 Tue May 20 18:46:17 2025
    ACUS11 KWNS 201845
    SWOMCD
    SPC MCD 201844 COR
    INZ000-ILZ000-202030-

    Mesoscale Discussion 0905
    NWS Storm Prediction Center Norman OK
    0144 PM CDT Tue May 20 2025

    Areas affected...much of central Illinois and adjacent west central
    Indiana

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

    Valid 201844Z - 202030Z

    CORRECTED FOR TYPO

    Probability of Watch Issuance...95 percent

    SUMMARY...Thunderstorm development will continue to gradually
    intensify through 2-4 PM CDT, posing increasing risk for severe
    weather.

    DISCUSSION...Low-level convergence and boundary-layer
    destabilization is becoming maximized across much of central
    Illinois, within the warm sector to the southeast of the primary
    surface low center now over southeastern Iowa. This will continue
    to be aided by mid-level cooling and forcing for ascent associated
    with a still well-defined cyclonic vorticity center to the
    west-northwest of Quincy IL, which is forecast to continue a slow
    northeastward and eastward migration across the Midwest through late afternoon.=20

    Thermodynamic profiles, particularly centered across and southeast
    of the Springfield area, appear characterized by rather steep lower/mid-tropospheric lapse rates, with mixed-layer CAPE increasing
    in excess of 1000 J/kg. As residual inhibition associated with the
    remnants of elevated mixed-layer air continues to erode, the
    environment is becoming supportive of organized convection
    near/beneath the exit region of a strong mid/upper jet. This may
    include a few discrete supercells and perhaps an organizing cluster
    with potential to produce severe hail and damaging wind gusts.=20=20

    Modest clockwise-curved low-level hodographs may also support a risk
    for tornadoes, particularly with the more discrete storms.

    ..Kerr/Hart.. 05/20/2025

    ...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!_NdVvgkx0Jx-PdPUdCiov8U_WCI8FOEt2xEOpcJvpQKViiZpMgi2oBhqNX_xwADtvBVo0uBrK= R4s0VX1J3wxAqM13hw$ for graphic product...

    ATTN...WFO...IND...LOT...ILX...LSX...DVN...

    LAT...LON 41188923 40728835 38858721 38988952 39868947 40358973
    41188923=20

    MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
    MOST PROBABLE PEAK WIND GUST...55-70 MPH


    =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 3.20-Linux
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)