Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Oct 24 2023 12:56:07 ACUS01 KWNS 241256 SWODY1 SPC AC 241254 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0754 AM CDT Tue Oct 24 2023 Valid 241300Z - 251200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTHWEST AND SOUTHERN HIGH PLAINS...AND THE UPPER MIDWEST... ....SUMMARY... Isolated severe thunderstorms capable of hail and/or wind are possible through tonight across parts of the Southwest into the southern High Plains, and over portions of the Upper Midwest. ....Southeast AZ to west TX... A shortwave trough centered on Baja CA will gradually shift east across northwest Mexico through tonight. Initially modest low-level southerlies will back and strengthen this evening into tonight across parts of west TX and the Permian Basin. This will aid in a plume of 600-1300 J/kg MLCAPE developing by late afternoon across parts of southwest to west-central TX and spreading northwest during the evening into southeast NM and the TX South Plains. The bulk of afternoon scattered storm development will occur to the west of this buoyancy plume across southeast AZ and southern NM closer to the stronger large-scale ascent. Moderately steep mid-level lapse rates should compensate for the initially meager buoyancy and yield an initial threat for isolated, marginally severe hail. This evening, as convection consolidates and impinges on the aforementioned modest buoyancy plume, broad clusters potentially evolving into a loosely organized QLCS should spread across southeast NM and parts of west TX into the early morning. A mix of strong to locally severe wind gusts along with a continued threat for marginally severe hail will be possible. ....Upper Midwest... An elevated MCS is ongoing from west-central Lower MI west across southern WI with a history of small hail below one inch. This activity will likely spread east but shift farther away from the elevated instability max centered on the NE/SD/MN/IA border area. As such, the threat for large hail appears rather limited. In its wake, stratus is noted in satellite imagery near and north of the quasi-stationary/slow-moving warm front that arcs from northwest IA across southeast MN into central WI. Guidance varies markedly in how far north the warm front will be able to advance with the 06Z NAM and 10Z HRRR decidedly farther north in WI compared to other 00Z HREF members. This lowers confidence in whether surface-based thunderstorm development can be sustained along the warm front. Initially elevated showers across eastern SD and northeast NE behind the surface front will likely increase in coverage and intensity later this morning as it impinges on the larger MUCAPE downstream and MUCIN erodes. This activity will spread across the Upper MS Valley towards northern Lake MI. Updrafts should largely emanate from elevated parcels and remain to the cool side of the surface front. This should yield a primary threat of sporadic/isolated severe hail embedded within a broad convective band this afternoon to early evening. ...Grams/Goss.. 10/24/2023 $$ = = = 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) .