Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Sep 27 2023 17:31:31 ACUS02 KWNS 271731 SWODY2 SPC AC 271729 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Wed Sep 27 2023 Valid 281200Z - 291200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Severe thunderstorms appear unlikely on Thursday. ....Synopsis... Broad upper troughing is forecast to persist from the Pacific Northwest/Great Basin into the northern High Plains on Thursday, supported by a series of shortwave troughs moving through it base. Lead wave in this series will begin the period extended from southern Saskatchewan through central MT, before then progressing quickly eastward. Surface low will take a similar track to this shortwave, with an attendant cold front pushing eastward across the Dakotas. Low-level moisture will be limited ahead of this front, keeping thunderstorm chances low. Another shortwave trough is forecast to move into the northern/central High Plains late Thursday night/early Friday morning, resulting in a dynamically enhanced low-level jet from the southern High Plains through the central Plains. Isentropic ascent across the frontal zone will support isolated thunderstorms. Vertical shear and buoyancy will remain modest, limiting the overall severe potential. Westerly flow aloft is expected to persist south of the primary troughing as well, helping to support continued lee troughing across the High Plains. Strong boundary-layer mixing is anticipated east of the lee troughing, with the highest likelihood for isolated thunderstorm development across the southern High Plains. Across the eastern CONUS, a weakening upper low will likely begin the period over southern Lower MI before gradually drifting northeastward into southwestern Ontario. An associated surface low is forecast to drift eastward across the OH Valley. A weak boundary will extend southwestward/westward from this low, with showers and thunderstorms reinforcing this boundary throughout the morning. Weak convergence is possible along this boundary during the afternoon, with some chance for afternoon/evening thunderstorm development from central KY into southwest MO and western/middle TN. Modest buoyancy and weak shear should limit the overall severe threat. ...Mosier.. 09/27/2023 $$ = = = 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) .