Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Feb 23 2024 19:51:08 ACUS01 KWNS 231951 SWODY1 SPC AC 231949 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0149 PM CST Fri Feb 23 2024 Valid 232000Z - 241200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... The risk for severe storms appears negligible across the U.S. through tonight. ....20Z Update... The primary, and increasing, thunderstorm development has become focused offshore, in a narrow pre-cold frontal corridor, downstream of one increasingly sheared short wave perturbation within broader-scale cyclonic, southwesterly mid-level flow. As this continues to overspread middle into southern Atlantic coastal areas late this afternoon through tonight, higher thunderstorm probabilities will remain offshore. However, near pre-frontal surface troughing still overspreading portions of northern Florida and southeastern Georgia into South Carolina, cooling aloft is contributing to steeping low-level lapse rates, with boundary-layer moisture sufficient to contribute to weak ongoing destabilization. This is already supporting the initiation of widely scattered weak thunderstorm development, which may persist across the South Carolina Piedmont into coastal plain, and portions of the southeast Georgia coastal plain vicinity, into early evening. West of the Appalachians, deepening convection is evident within a narrow plume of warmer low-level air/stronger boundary-layer heating spreading into the Allegheny and Cumberland Plateau vicinity. Lightning has recently been detected across parts of northwestern Alabama into northern middle Tennessee, and further convective development capable of generating occasional lightning beneath seasonably mid-level air remains possible. Based on various ensemble output and NAM/Rapid Refresh forecast soundings, this potential (though with probabilities generally near the minimum threshold for a categorical thunder area) may become maximized across parts of the Allegheny Plateau late this afternoon, perhaps aided by somewhat stronger mid/upper forcing for ascent overspreading that region. ...Kerr.. 02/23/2024 ..PREV DISCUSSION... /ISSUED 1003 AM CST Fri Feb 23 2024/ ....Carolinas... Morning surface analysis shows a low over VA with a trailing cold front extending southwestward into the Gulf Coast states. This front will sweep southeastward today across the Carolinas. Cloud cover is diminishing across SC ahead of the front, which should result in some heating/destabilization. However, this heating will be behind a pre-frontal trough, where veering surface winds are weakening low-level convergence and shear. Cold temperatures aloft and steep lapse rates may still result in a few afternoon thunderstorms, with small hail possible in the stronger cells. However, guidance appears less favorable for severe storms than earlier anticipated. $$ = = = 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) .