Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jun 20 2023 05:51:37 ACUS01 KWNS 200551 SWODY1 SPC AC 200550 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Tue Jun 20 2023 Valid 201200Z - 211200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS...AND PARTS OF THE LOWER MISSISSIPPI VALLEY AND SOUTHEAST... ....SUMMARY... Isolated to scattered severe thunderstorms appear possible across parts of the Southeast and northern Plains today. Damaging winds and large hail should be the main threats. ....Synopsis... A highly amplified flow field aloft will prevail across the U.S. today, with a sharp trough over the West and a low over the Southeast, flanking a ridge extending from Texas to the Upper Great Lakes. At the surface, a weak baroclinic zone is progged to lie in an east-to-west manner across the Southeast/Gulf Coast states, and then turning northwestward across Texas to the central High Plains area. Meanwhile, a second cold front will make very gradual eastward progress across the Dakotas/Wyoming through the period. ....Northern Plains... Afternoon thunderstorm development is initially expected over the central Wyoming vicinity, with isolated storms then moving quickly northeastward. These storms would be accompanied by some potential for strong/gusty winds locally. By early evening, additional storm development is expected farther east, within the more unstable airmass along the surface cold front. With the eastern fringe of stronger mid-level southwesterlies expected to extend east atop the surface frontal zone, and a southerly low-level jet increasing through the evening, shear will support organized/rotating storms, accompanied by risks for severe-caliber hail/wind. While convection should diminish somewhat in coverage by late evening and into the overnight hours, local severe risk may persist through Wednesday morning, with lingering convection. ....Arklatex and Sabine River Valley east to southern Georgia and Florida... Widespread storms are expected once again today across portions of the Southeast and lower Mississippi Valley, as a very moist boundary layer -- destabilizing through the afternoon -- persists near and south of a weak surface baroclinic zone. While some risk for severe weather will exist as far east as Georgia/Florida, the greatest potential -- mainly in the form of damaging winds -- will likely occur from the Louisiana vicinity east to the Mobile Bay area. Here, stronger northwesterly cyclonic flow aloft -- around the back side of the upper low parked over the Mid South -- is expected. Episodes of strong/locally severe storms through much of the period. ...Goss/Wendt.. 06/20/2023 $$ = = = 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) .