Subj : MESO: Mesoscale Discussion 0025 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jan 03 2023 20:07:40 ACUS11 KWNS 032007 SWOMCD SPC MCD 032006=20 ILZ000-MOZ000-032230- Mesoscale Discussion 0025 NWS Storm Prediction Center Norman OK 0206 PM CST Tue Jan 03 2023 Areas affected...South-central Illinois Concerning...Severe potential...Watch unlikely=20 Valid 032006Z - 032230Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong to severe thunderstorms are possible across south-central IL this afternoon. Locally damaging gusts, isolated large hail, and a tornado or two are possible. DISCUSSION...Water-vapor imagery and regional VWP data show a mid-level speed max over MO approaching portions of western IL, where a north-south oriented baroclinic zone is moving eastward. As the related large-scale ascent overspreads the front, isolated thunderstorm development is possible in the vicinity of the front. Storm development will be aided by continued boundary-layer moistening/heating and related destabilization in the presence of large-scale ascent. In fact, a few showers are developing along the baroclinic zone southeast of St. Louis. Ahead of the front, lower 60s dewpoints beneath cold temperatures aloft will contribute to moderate surface-based instability amid strengthening deep-layer shear characterized by long, generally straight hodographs (45-50 kts effective bulk shear oriented oblique to the front). As a result, a couple of loosely organized, splitting supercell structures are possible in south-central IL this afternoon. Large hail and a tornado or two are possible with the initial discrete activity. With time, cell interactions and localized upscale growth could favor a greater damaging-wind risk with eastward extent. While clouds have cleared over western IL, lingering cloud cover over eastern IL casts uncertainty on robust, sustained storm development. A watch issuance is not expected, though trends will be monitored. ...Supinie/Weinman/Hart.. 01/03/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!6oB7o7htZozcY4UJk28lptnUUynnNFeOc6r4Z4H1qGmOIck5ATT9AMqrMFAGfrB_Wa5cWmM0O= YLhUczTzUwspyXqvQA$ for graphic product... ATTN...WFO...PAH...LOT...ILX...LSX... LAT...LON 38448815 38058863 37738914 37678954 38009008 38469011 39228999 39688978 40078948 40288913 40498849 40448786 40218770 39728762 39188773 38448815=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) .