Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Feb 12 2025 16:46:14 ACUS01 KWNS 121646 SWODY1 SPC AC 121644 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1044 AM CST Wed Feb 12 2025 Valid 121630Z - 131200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF LOUISIANA/MISSISSIPPI/ALABAMA... ....SUMMARY... Severe thunderstorms are expected this afternoon through late tonight from the Lower Mississippi Valley into Georgia. The main potential is for damaging winds and tornadoes, a few of which could be strong (EF2+). ....Lower Mississippi Valley to Southeast States... As a longwave trough amplifies over the Great Plains, strengthening cyclonically influenced deep-layer southwesterly winds will partially overlie an increasingly moist/unstable northward-shifting warm sector today, with storms expected to steadily increase in coverage and intensity through the afternoon especially across parts of Louisiana/Mississippi into Alabama. Early morning analysis features a northward-shifting maritime warm front just inland from, and parallel to, the Gulf coast, with near-70F surface dewpoints becoming increasingly common as of 9am CST/15z from the upper Texas Coast to near the New Orleans Metro and Alabama/Florida border vicinity. Similarly, even prior to the warm front arrival, the KLIX 12z observed sounding sampled a 1.63 inch Precipitable Water and 13.3 g/kg mean mixing ratio, which are in the upper 5-10 percent of daily climo values, illustrating the quality of near-coastal low-level moisture. While multi-layer cloud cover is prevalent north of the warm front, more aggressive heating/isolation is evident in proximity to the Gulf coast with deepening cumuliform development within the warm sector. These trends in concert with short-term guidance suggest that MLCAPE will exceed 1000 J/kg especially across southeast Louisiana, the southern half of Mississippi into southwest Alabama by mid/late afternoon. Expect warm sector storm development to begin during the early afternoon once convective inhibition erodes. Given the strength of deep-layer shear and expected low-level curvature, some supercells capable of all severe hazards, including tornadoes, are possible. A few strong tornadoes are possible. In particular, short-term guidance advertises a notable increase in southwesterly 850 winds (lowest 1-2km AGL) by early evening (circa 00z) across Mississippi/Alabama, which could enhance potential for supercell sustenance and stronger tornado potential late this afternoon through evening. Another round of thunderstorms is anticipated during the evening and overnight as the cold front accelerates east-southeastward across the region. The strength of these storms could be modulated by the coverage of the preceding afternoon storms, with greater storm coverage reducing buoyancy. However, current expectation is that persistent low-level theta-e advection will allow for airmass recovery, and that strong to severe storms are likely within this convective line. Primary severe risk with the line is damaging gusts, but low-level shear will remain strong enough to also support the potential for QLCS-related tornadoes as well. ...Guyer/Moore.. 02/12/2025 $$ = = = 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) .