Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Feb 17 2025 06:49:30 ACUS02 KWNS 170649 SWODY2 SPC AC 170647 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1247 AM CST Mon Feb 17 2025 Valid 181200Z - 191200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS AND SOUTHERN LOUISIANA... ....SUMMARY... A couple of strong to severe thunderstorms are expected to evolve across southeast Texas and portions of southern Louisiana, mainly Tuesday evening and into the overnight hours. ....Upper TX Coast and Southern LA... An upper shortwave trough will move across the Plains to the MS Valley on Tuesday. This will bring a swath of enhanced mid/upper-level southwesterly flow across the south-central states. At the surface, a weak low will traverse the western Gulf Coast vicinity to southern MS through the period. Meanwhile, an Arctic cold front will surge south/southeast across the region mainly after 00z and into Wednesday morning. Ahead of the cold front, southerly near-surface flow and a strengthening southwesterly low-level jet will transport 60s F dewpoints northward. However, the northward extent of deeper moisture return will be limited to near the I-10 corridor. A cool boundary-layer beneath a warm layer between 925-850 mb will result in little surface-based instability. Additionally, nebulous large-scale ascent will preclude convective development until near 00z when the upper trough impinges on the area. Cooling aloft and modestly steep midlevel lapse rates amid moistening low/midlevels will support MUCAPE values up to around 1000 J/kg. Vertical shear will be favorable for organized convection, with elongated/straight hodographs forecast above the aforementioned warm layer. While the warm sector will be rather limited, and the cold front will quickly surge southeast after dark, a few stronger elevated storms will be possible. This activity will mainly pose a risk for marginally severe hail. There is some conditional potential toward the end of the period for near-surface based convection across parts of southern LA. However, this is conditional on the northward extent of the warm sector, which remains uncertain as the surface low is forecast to track very near the coast. If near-surface based storms can develop, some potential for strong gusts and a tornado or two will accompany storms given very favorable low-level SRH and large/curved low-level hodographs. Will include low tornado probabilities to encompass this scenario, though this outcome remains uncertain. ...Leitman.. 02/17/2025 $$ = = = 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) .