Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Feb 09 2023 16:28:45 ACUS01 KWNS 091624 SWODY1 SPC AC 091622 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1022 AM CST Thu Feb 09 2023 Valid 091630Z - 101200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON ACROSS PARTS OF NORTHERN AND WESTERN GEORGIA INTO SOUTHEASTERN ALABAMA AND THE WESTERN FLORIDA PANHANDLE... ....SUMMARY... A couple of strong thunderstorms are possible in a corridor across the Georgia Piedmont into southeastern Alabama and the Florida Panhandle this afternoon. These may pose a risk for producing locally damaging wind gusts. ....Synopsis... On the leading edge of an amplified belt of westerlies emanating from the mid-latitude Pacific, a vigorous short wave trough is forecast to continue digging to the lee of the southern Rockies. In its wake, the center of a prominent cold surface ridge will continue to build south-southeastward across the southern Rockies vicinity, with the leading edge of the cold intrusion likely reaching the lower Rio Grande Valley by late tonight. A preceding cold front is expected to steadily progress into and across the Appalachians and northwestern Gulf of Mexico, in the wake of a broad and relatively deep, occluding cyclone. This cyclone is accompanying a significant mid-level impulse forecast to accelerate northeast of the lower Great Lakes region through the St. Lawrence Valley, as an upstream short wave trough digs into the Upper Midwest, and fairly prominent mid-level ridging (centered near the Bahamas) is maintained near/east of the southeastern Gulf of Mexico and Atlantic Seaboard. ....Eastern U.S.... A combination of weak/limited low-level moisture return, relatively warm mid-levels with weak lapse rates, and in some areas a residual near-surface stable layer will tend to minimize the risk for thunderstorm development in the warm sector of the surface cyclone. One area where at least some model output (perhaps most notably the Rapid Refresh) suggests that weak boundary-layer destabilization may occur is a narrow pre-cold frontal corridor across the Piedmont of east central Alabama into northern Georgia. It appears that this will largely hinge on sufficient thinning and breaks of current cloud cover, but with some insolation the environment may become conducive to scattered thunderstorm development. If this occurs, downward mixing of 30-50 kt south-southwesterly to southwesterly flow in the 850-500 mb layer may contribute to a risk for localized potentially damaging wind gusts. Otherwise, with better boundary-layer moisture and instability now generally offshore, weakening lower/mid-tropospheric wind fields across eastern Gulf coastal areas appear to be leading to diminishing convective potential inland of the coast through the remainder of the period. ...Kerr/Supinie.. 02/09/2023 $$ = = = 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) .