Subj : MESO: Mesoscale Discussion 2331 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun Dec 17 2023 02:00:11 ACUS11 KWNS 170200 SWOMCD SPC MCD 170159=20 FLZ000-170430- Mesoscale Discussion 2331 NWS Storm Prediction Center Norman OK 0759 PM CST Sat Dec 16 2023 Areas affected...portions of the southern and central Florida Peninsula and Keys Concerning...Severe potential...Watch possible=20 Valid 170159Z - 170430Z Probability of Watch Issuance...60 percent SUMMARY...Strong to potentially severe thunderstorms may move ashore from the Gulf of Mexico over the next several hours. Isolated tornadoes and damaging gusts are the main threats. The need for a Tornado Watch issuance depends on how much instability can precede the approaching line of thunderstorms. DISCUSSION...A surface low continues to deepen across the eastern Gulf of Mexico and approach the FL Peninsula as an upper-level trough continues to amplify over the MS Valley. A confluence band preceding the aforementioned surface low is comprised of convection that has percolated in intensity over the last few hours, and is poised to move ashore sometime before Midnight EST. Widespread rain and convection have been overspreading the Peninsula for much of the day, with 00Z soundings over TBW and MFL depicting low/mid-level lapse rates barely exceeding 5 C/km. Despite low 70s F dewpoints, buoyancy has been meager so far, though gradual increases in instability are possible across southern FL tonight.=20 Shear profiles are impressive ahead of the rapidly deepening surface low, with the same aforementioned observed soundings showing very large, curved hodographs in the 0-3 km layer. As such, it is not out of the question for a few damaging gusts or tornadoes to occur if a persistent updraft can develop and ingest any available surface-based, unstable parcels. As such, conditions are being monitored for the need of a Tornado Watch issuance. ...Squitieri/Smith.. 12/17/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!9qbGm4lVLh1say_GDeEjUbcsOTIYl3dK_IgvSJEkwZRYCwE6ZBQl-C_p_KodQE42m4M6vs2i2= kp6a9Nbj38ciY_hOMA$ for graphic product... ATTN...WFO...MFL...MLB...KEY...TBW...JAX... LAT...LON 24618209 24878158 25198122 25618137 26378205 27288262 28458282 29388200 29538127 29238091 28188054 26878006 25978004 25268010 24788047 24528111 24488169 24618209=20 =3D =3D =3D 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) .