Subj : MESO: Mesoscale Discussion 1329 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jun 29 2023 07:21:31 ACUS11 KWNS 290721 SWOMCD SPC MCD 290720=20 ILZ000-290945- Mesoscale Discussion 1329 NWS Storm Prediction Center Norman OK 0220 AM CDT Thu Jun 29 2023 Areas affected...Portions of central/southern IL Concerning...Severe potential...Watch possible=20 Valid 290720Z - 290945Z Probability of Watch Issuance...60 percent SUMMARY...The threat for severe hail with elevated supercells may increase over the next few hours. Watch issuance is possible. DISCUSSION...Recent IR satellite imagery shows cooling cloud tops with developing convection across parts of central IL. This activity is likely being aided by low-level warm advection and related ascent on the nose of a 25-35 kt southwesterly low-level jet that extends across MO into central IL. A sharp instability gradient is also present over IL based on latest mesoanalysis, extending almost due north to south into western KY. The convection appears to be developing along this MUCAPE gradient, and most high-resolution guidance suggests these thunderstorms will increase in both coverage and intensity over the next few hours. The initial thunderstorms may be elevated supercells given a veering/strengthening wind profile with height through mid levels, and 40-50 kt of deep-layer shear. Large hail should be the main threat with these supercells. Some potential will also exist for upscale growth into small bowing clusters, which would probably tend to develop south-southeastward along the instability gradient. Severe/damaging winds would become an increasing threat with any cluster that develops, as a large reservoir of buoyancy and strong DCAPE should partially offset the MLCIN present. Convective trends will be monitored for possible watch issuance. ...Gleason/Thompson.. 06/29/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!9Fyq0Jwmjv9D8eEQv87AHieUT3a6JXgjDlHVTt41c_qXRt6-2B7bbzXE83PbPfZ7AB9J7xavH= mR-blivGAVl3ZtXVDk$ for graphic product... ATTN...WFO...PAH...LOT...ILX...LSX... LAT...LON 38718958 39458992 40529038 41079021 41088887 40728831 40008792 39218779 38468784 38228830 38238914 38718958=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) .