Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Feb 11 2025 19:55:36 ACUS01 KWNS 111955 SWODY1 SPC AC 111953 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Tue Feb 11 2025 Valid 112000Z - 121200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH TEXAS AND THE SOUTHEAST... ....SUMMARY... Isolated strong to severe thunderstorms are possible from south Texas into parts of Mississippi and Alabama through tonight. ....20z Update... The prior forecast remains largely unchanged with minor adjustments to the thunder area. A well-defined cold front, quickly moving over the southern Plains and western MS valley, will likely continue to undercut the modified Gulf air mass over parts over southern TX. Increasing large-scale ascent over the western edge of the moist sector and cold front will support a gradual increase in convective coverage over south-central and west TX this evening and into the overnight hours. Weak to moderate elevated buoyancy and 40-50 kt of effective shear could support a few organized elevated supercell or bowing structures with a risk of hail or an isolated damaging gust over south TX tonight. Weak buoyancy will also likely extend across northern OK and the Ozarks supporting a risk for scattered thunderstorms. Have extended the thunder area farther northeast for lightning potential late tonight. Across the southeast, recent model guidance suggests storms may persist a bit farther east into parts of AL/GA. While buoyancy will be very weak, inland advection of upper 50s to low 60s F dewpoints could sustain some elevated thunder potential late tonight. ...Lyons.. 02/11/2025 ..PREV DISCUSSION... /ISSUED 1029 AM CST Tue Feb 11 2025/ ....South TX to MS/AL through tonight... Clusters of thunderstorms are ongoing near a surface cold front in the Houston area, on the edge of surface temperatures in the low 70s with dewpoints near 70 F. The proximity VWP from HGX shows modest low-level shear/hodograph curvature and stronger flow above 5 km AGL, with some potential for organized storm structures within the band. However, the cold front is also tending to undercut the storms, which casts doubt on the severe storm potential in the short term. Farther east, warming temperatures in cloud breaks and a gradual increase in low-level moisture will result in modest destabilization through the afternoon. 12z regional soundings suggest that midlevel lapse rates will remain relatively poor, though surface temperatures of 75-80 F and boundary-layer dewpoints in the mid 60s will drive MLCAPE of 500-1000 J/kg. Shallow convection is likely in the open warm sector, but thunderstorm potential will be focused along the front where low-level ascent will be maximized later this afternoon/evening. Assuming a couple of storms can form along the front, there will be the potential for isolated wind damage and perhaps a tornado. Overnight, thunderstorm coverage should increase along and immediately north of the front across south central TX, as a midlevel shortwave trough near Baja ejects east-northeastward. Midlevel lapse rates in the 7.5-8.5 C/km range and moistening atop the frontal surface will support MUCAPE near or above 1000 J/kg, while effective bulk shear in excess of 40 kt/long hodographs will be sufficient for elevated organized/supercell storms capable of producing isolated large hail and possibly wind damage. $$ = = = 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) .