Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Nov 24 2022 05:42:31 ACUS01 KWNS 240542 SWODY1 SPC AC 240541 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1141 PM CST Wed Nov 23 2022 Valid 241200Z - 251200Z ....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH-CENTRAL TEXAS TO SOUTHWEST LOUISIANA... ....SUMMARY... A few strong to severe storms are possible Thursday from south-central Texas into southwest Louisiana. Locally damaging wind gusts are the primary threat. ....TX/LA... Upper trough continues to dig south across the central Rockies and will soon develop a closed circulation over NM. This feature is forecast to settle into far west TX by the end of the period as strongest mid-level flow will not round the base of the trough until later in the day2 period. As a result, meager height falls will overspread the warm sector, and this will be primarily across the Edwards Plateau region during the early-mid afternoon hours. Late this evening, scattered-numerous showers/thunderstorms have evolved within a zone of low-level warm advection beneath the LLJ that extends from central TX-southeast OK-western AR. Latest guidance suggests LLJ will weaken considerably through Thursday evening then increase overnight across the lower MS Valley where it should encourage another bout of concentrated convection during the latter half of the period from LA into AL. Instability is expected to remain meager within these warm advection zones and forecast soundings do not favor organized severe. In the absence of meaningful large-scale forcing spreading into TX during the day1 period, boundary-layer heating is expected to prove instrumental in potential robust thunderstorm development. One area where a few strong storms may evolve will be ahead of the surging cold front across the Edwards Plateau during the afternoon. Latest data suggests partial heating across this region could aid destabilization such that surface-based parcels become buoyant by 19z. NAM forecast sounding for Brownwood at 19z exhibits SBCAPE around 1300 J/kg with 35kt surface-6km bulk shear and a veering wind profile with height. This would seemingly support some supercell potential and have extended low severe probabilities into this region of TX to account for wind/hail with isolated afternoon convection. Downstream, extensive precipitation across eastern TX, along with a weakening LLJ should allow a weak surface boundary to sag south into the lower Sabine River Valley, arcing west across the upper TX Coastal Plain. PW values should gradually increase across this region but forecast buoyancy is not expected to be that significant. Latest water-vapor imagery suggests a weak low-latitude short-wave trough ejecting northeast across northern Mexico toward south TX. This feature should encourage a considerable amount of convection north of the boundary with scattered storms expected to spread across much of the Coastal Plain. Strong, deep-layer flow and adequate shear will exist for at least the threat of locally severe wind gusts with this activity. ...Darrow/Squitieri.. 11/24/2022 $$ = = = 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) .