Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Feb 13 2025 05:42:19 ACUS01 KWNS 130542 SWODY1 SPC AC 130540 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1140 PM CST Wed Feb 12 2025 Valid 131200Z - 141200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE FLORIDA PANHANDLE INTO SOUTHERN GEORGIA AND PARTS OF THE CENTRAL VALLEY OF CALIFORNIA... ....SUMMARY... Isolated, marginally severe storms are possible from the Florida Panhandle into southern Georgia and parts of the Central Valley of California. Damaging winds and a brief tornado are the primary threats. ....Southeast... A large-scale upper trough will shift east from the MS Valley into the Great Lakes and the central Appalachians during the day and become increasingly displaced from the northeast Gulf Coast. Likewise, a surface low initially near Lakes Erie/Ontario will develop northeast into the St. Lawrence Valley as a trailing cold front pushes southeast through the northeast Gulf Coast/Southeast U.S. A band of showers/thunderstorms will be ongoing at the start of the period from the FL Panhandle north-northeastward into south-central GA and SC. The severe risk will likely focus during the morning as the environment will support enlarged hodographs within a moist/weakly unstable warm sector (250-750 J/kg MLCAPE) ahead of the cold front. Storm intensity will likely diminish considerably during the afternoon as the southern periphery of an 850-mb speed max shifts northeast. A few stronger storms embedded within the band may be associated with a threat for damaging gusts and perhaps a tornado before this threat wanes. ....Central Valley of California... A powerful mid-level trough over the eastern Pacific will move inland during the day and reach the Great Basin tonight. Initial shower activity associated with strong low-level warm-air advection will move east/south by the early to mid afternoon. A period of weak destabilization is expected by the mid-late afternoon due in part to strong mid-level cold-air advection (500-mb temperatures cooling into the -22 to -25 deg C range). As a result, the steepening of lapse rates may yield upwards of 250 J/kg SBCAPE. Low-topped convection is currently progged in the latest convection-allowing model guidance in the central valley. Forecast soundings show relatively moist/near-saturated low levels coincident with strengthening and veering flow with height in the lowest 3 km. A couple of stronger updrafts may exhibit transient rotation and potentially yield a localized wind/brief tornado risk during the late afternoon. ...Smith/Weinman.. 02/13/2025 $$ = = = 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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .