Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Oct 12 2023 06:00:34 ACUS02 KWNS 120600 SWODY2 SPC AC 120558 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Thu Oct 12 2023 Valid 131200Z - 141200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSISSIPPI VALLEY AND MIDWEST... ....SUMMARY... Thunderstorms capable of producing isolated damaging winds may occur Friday across parts of the mid Mississippi Valley and Midwest. Some threat for marginally severe hail and perhaps a tornado or two may also exist across parts Iowa into northern Missouri and far west-central Illinois. ....Mid Mississippi Valley/Midwest... A line/cluster of thunderstorms will probably be ongoing at the start of the period Friday morning across parts of the mid MS Valley in association with a southerly low-level jet and related warm advection. This activity should tend to remain sub-severe as it spreads eastward into IL and vicinity through the morning. But, some chance for strong/gusty winds may exist, especially on the southern flank of the line in east-central MO into central IL where slightly greater low-level moisture and weak instability should be present. In the wake of this morning activity, additional convection appears possible near and east of a surface low which should be centered along the IA/MO border by early Friday afternoon. A pronounced upper trough associated with this surface low is forecast to continue eastward across the Midwest through Friday evening. Cold temperatures at mid levels along with modest daytime heating should aid the development of weak instability along/south of a warm front that should be located over parts of IA/IL. Given sufficient deep-layer shear, some of this convection may become organized and pose an isolated threat for damaging winds, marginally severe hail, and perhaps a tornado or two. The hail and tornado threat should be focused along/near the warm front and surface low in IA, northern MO, and west-central IL. Otherwise, strong to damaging winds should be the primary severe hazard across a broader portion of the mid MS Valley into the Midwest, where sufficient boundary-layer instability can develop to support surface-based thunderstorms. In general, poor lapse rates and weak forecast instability should keep the overall severe threat fairly isolated/marginal. ...Gleason.. 10/12/2023 $$ = = = 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) .