Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Feb 04 2024 05:54:58 ACUS01 KWNS 040554 SWODY1 SPC AC 040553 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1153 PM CST Sat Feb 03 2024 Valid 041200Z - 051200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTHERN PORTIONS OF THE FLORIDA PENINSULA INTO THE FLORIDA KEYS... ....SUMMARY... Isolated to scattered severe thunderstorms will be possible over parts of the Florida Peninsula from late morning to early evening. A brief tornado or two will be possible along a portion of the central California coast, mainly in the afternoon. ....Synopsis... A 500 mb cyclone will track across the Gulf Coast region as a second mid-level trough impinges on the West Coast today. Multiple mid-level impulses will pivot around the Gulf Coast upper low, supporting surface cyclogenesis near the FL Peninsula. Low-level moisture return will precede surface cyclone arrival, supporting multiple rounds of strong to potentially severe thunderstorms across the FL Peninsula through the day. Meanwhile, a surface low will also approach the CA coastline in tandem with the aforementioned mid-level trough, allowing for some low-level moisture return amid strong forcing for ascent. Adequate (albeit scant) buoyancy should materialize during the day along the CA coast, fostering some potential for isolated severe thunderstorms. ....Florida Peninsula and Keys today into tonight... The first impulse pivoting around the upper low will support surface cyclogenesis just west of the FL Peninsula at the start of the period. Low to mid 60s F surface dewpoints should return across the FL Keys into the far southern parts of the peninsula ahead of an approaching QLCS during the morning hours. 6-7 C/km mid-level lapse rates may overspread the modifying airmass, promoting up to 500 J/kg SBCAPE prior to QLCS arrival. Forecast soundings depict enlarged, curved low-level hodographs, with 200-300 m2/s2 0-3 km SRH possible. As such, embedded supercell structures or mesovortices may develop within the QLCS across far southern FL into the Keys, accompanied by threats for damaging gusts and isolated tornadoes. QLCS arrival should be within the 12-16Z time frame. A sparse damaging gust/tornado threat also exists across the rest of the peninsula as the surface low and associated QLCS tracks northeast through the morning hours, though the severe threat may be limited by weaker instability. The passage of the QLCS will give way to stronger diurnal heating and airmass modification across the FL Peninsula during the afternoon hours. Guidance consensus suggests that an MCS may organize over the central Gulf and rapidly progress toward the peninsula by evening in tandem with the approach of another mid-level impulse. However, this MCS may not reach the western FL Peninsula until well after dark. Given nocturnal cooling and stabilization, questions remain regarding how strong convection will be. Still, at least a damaging gust or two is possible. ...California Coast today... Strong low-level warm-air advection, accompanied by scattered showers and thunderstorms, should transpire over CA through much of the day as a surface low approaches the coast. Strong cooling with height given the overspreading mid-level trough will steepen mid-level lapse rates to at least 7 C/km, boosting SBCAPE up to or just over 500 J/kg by afternoon. At the same time, tropospheric winds will intensify, with winds also veering and intensifying with height to support elongated, curved hodographs. Any stronger storms that can approach the CA coast during the afternoon hours and achieve supercell structures will have the best chance at producing a damaging gust or brief tornado. ...Squitieri/Kerr.. 02/04/2024 $$ = = = 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) .