Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Mar 03 2023 16:13:04 ACUS01 KWNS 031612 SWODY1 SPC AC 031611 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1011 AM CST Fri Mar 03 2023 Valid 031630Z - 041200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS TN/OH VALLEYS TO THE SOUTHERN APPALACHIANS... ....SUMMARY... Numerous tornadoes and scattered swaths of severe damaging winds are probable into this evening from the Tennessee to Ohio Valleys towards the southern Appalachians. A few tornadoes may be strong (EF-2) with the greatest chance across parts of Kentucky and Tennessee. ....TN to OH Valleys and the central/southern Appalachians... Two primary areas of convective activity are ongoing from MS/AL/TN border area northwest to the confluence of the MS/OH Rivers. Leading pre-frontal squall, low-topped near the central MS/AL border with progressively deeper tops northward, will likely persist east-northeast this afternoon and reach the southern Appalachians by early evening. With broken cloudiness across AL and richer boundary-layer moisture, sampled by the 12Z LIX sounding, advecting north from the central Gulf Coast, this QLCS should ingest the northern gradient of peak surface-based buoyancy. This should result in intensification of the squall line with embedded QLCS tornadoes and damaging winds as the primary hazards. Farther north, broken convective bands are evident along the northern periphery of the warm sector near the MS/OH Rivers confluence, close to the deep surface cyclone. A robust surface pressure rise-fall couplet and the extreme low to deep-layer shear should compensate for the meager surface-based buoyancy and likely yield a mix of low-topped supercells and quasi-linear bowing segments, as convection rapidly spreads east-northeast. Tornadoes should be realized in sustained supercells and line-embedded mesovortices, a few of which could be significant. Given the supercell wind profiles and morning CAMs suggesting more broken convection, damaging winds will probably consist of scattered swaths of severe gusts from 60-80 mph. Severe potential today will be limited on the southern part by weakening DCVA and frontal convergence with southward extent, on the northern end by northward loss of boundary-layer destabilization away from the warm-frontal zone, and to the east by loss of both daytime heating and overall lift. As such, the unconditional probability gradient is kept rather broad on both sides, though the actual southern/northern/eastern cutoffs of severe could be abrupt. ...Grams/Wendt.. 03/03/2023 $$ = = = 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) .