Subj : MESO: Mesoscale Discussion 1369 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Jul 01 2023 16:29:00 ACUS11 KWNS 011628 SWOMCD SPC MCD 011628=20 KYZ000-TNZ000-INZ000-ILZ000-MOZ000-ARZ000-011800- Mesoscale Discussion 1369 NWS Storm Prediction Center Norman OK 1128 AM CDT Sat Jul 01 2023 Areas affected...portions of northern AR...southern MO/IL...into western KY/TN Concerning...Severe potential...Severe Thunderstorm Watch likely=20 Valid 011628Z - 011800Z Probability of Watch Issuance...80 percent SUMMARY...Severe thunderstorm potential will increase through early afternoon across portions of the Ozarks to the Mid-Mississippi/Lower Ohio Valleys. Damaging gusts and large hail will be possible with thunderstorm activity through the afternoon. DISCUSSION...An expansive, increasingly agitated cumulus field is noted in visible satellite imagery late this morning from northern Arkansas into southern Missouri toward the confluence of the Ohio/Mississippi Rivers. Latest objective mesoanalysis data suggests low-level inhibition has quickly eroded as strong heating occurred through the morning hours, and temperatures have rapidly warmed into the low 90s. Generally 70s F dewpoints are contributing to increasing destabilization, with MLCAPE values ranging from 1500-3500 J/kg across the region. These factors will likely result in somewhat early convective initiation across the region ahead of a midlevel shortwave impulse now entering southwest MO.=20 Bulk effective shear from 25-35 kt will allow for organized cells/clusters. Given relatively modest midlevel flow, some upscale development may occur via consolidating outflows via storm interactions and/or generation of a sufficient cold pool. If this occurs, a bowing line of convection may shift generally east across western KY/TN. If a well organized bow emerges, the risk for more widespread damaging (and possibly isolated significant gusts) would increase. However, this scenario remains rather uncertain. Nevertheless, thunderstorm clusters will still be capable of severe/damaging gusts given strong instability and steep low-level lapse rates. Current thinking for convective evolution aligns more with CAM solutions from the NSSL/ARW rather than the HRRR, as the former solutions appear to have a better handle on current observed trends. While some uncertainty exists regarding timing and aerial extent, a severe thunderstorm watch will likely be needed in the next hour or so. ...Leitman/Grams.. 07/01/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!5nRXCN3ZpzhxCzTMET4jrCDMmDZ8nY2pIyOEMHma2YNG9ukQo-DrviVv-12X6tPFsvvRqwyB8= pmqiZfk0OSFSnwmSvk$ for graphic product... ATTN...WFO...LMK...OHX...PAH...MEG...LSX...LZK...SGF... LAT...LON 35588774 35158912 35049047 35219171 35729282 36559318 37039294 37429236 37879081 38238940 38128822 37808751 37068671 36518671 35588774=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) .