Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu May 16 2024 06:00:56 ACUS02 KWNS 160600 SWODY2 SPC AC 160559 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ....SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ....East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ....Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ...Mosier.. 05/16/2024 $$ = = = 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) .