Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Aug 19 2023 06:39:55 ACUS03 KWNS 190639 SWODY3 SPC AC 190638 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0138 AM CDT Sat Aug 19 2023 Valid 211200Z - 221200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... The risk for severe thunderstorms currently appears negligible across the U.S., Monday through Monday night. ....Discussion... A large, strong mid-level ridge will remain centered across the central Great Plains/lower Missouri Valley, and maintain a considerable influence across much of the nation, from the Rockies into the Mid Atlantic and Southeast, through this period. Within a confluent regime between this feature and mid-level troughing very slowly migrating inland across the Pacific Northwest, the weakening mid-level remnants of Hilary are forecast to accelerate across the northern Intermountain Region and Rockies into the Canadian Prairies. At the same time, weak mid-level troughing will be maintained near the U.S. Pacific Coast, a wave in the easterlies to the south of the ridge may approach the lower Texas coast, and large-scale mid-level troughing may continue to dig off the North Atlantic coast. Moderate to strong potential instability may develop across parts of the mid/lower Missouri into Ohio Valleys, to the south and west of a cold front advancing to the southeast of the St. Lawrence Valley and Great Lakes region. However, it appears that mid-level inhibition and weak forcing for ascent will suppress sustained thunderstorm development. Models do suggest that a strengthening southwesterly low-level jet, to the east of a weak frontal wave across the northern Great Plains into Upper Midwest, may contribute to elevated destabilization across parts of east central Minnesota into northern Wisconsin by late Monday night. It is possible that this could support scattered thunderstorm development with potential to produce small to marginally severe hail, but confidence is not yet high enough to introduce 5 percent probabilities at this time. Otherwise, seasonably moderate to strong south/southwesterly monsoonal flow around the western periphery of the mid-level ridge, across much of the Intermountain Region into northern Rockies, may contribute to at least some potential for thunderstorms capable of producing strong to severe surface gusts. However, due to generally weak forecast instability, it is possible that any such activity may remain rather sparse (less than 5 percent probability) in coverage. ...Kerr.. 08/19/2023 $$ = = = 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) .