Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Jan 18 2023 16:32:11 ACUS01 KWNS 181632 SWODY1 SPC AC 181630 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Jan 18 2023 Valid 181630Z - 191200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SABINE AND LOWER MS/OH VALLEYS... ....SUMMARY... A few tornadoes and scattered damaging winds remain possible this afternoon from the Sabine Valley to the Mid-South, with more isolated coverage continuing into this evening across the Lower Ohio and Mississippi Valleys. ....Sabine and Lower MS/OH Valleys... Minimal change apparent for this outlook with a broken band of thunderstorms within the warm conveyor ahead of the eastern-moving cold front. The severe threat will likely peak this afternoon from the Sabine Valley into the Mid-South where 60s surface dew points (increasing to the southwest) supports MLCAPE of 500-1000 J/kg. The orientation and track of the shortwave trough over the central Great Plains suggests that mid-level lapse rates will weaken this afternoon, along with increasingly veered low-level flow diminishing hodograph curvature over the southern portion of the convective threat in TX/LA. This will likely maintain STP values in the 1-2 range this afternoon before diminishing later. A few tornadoes appear possible, with the damaging wind threat increasing some as the broken line consolidates into a broader QLCS. Confidence is decreasing with the longevity of an appreciable tornado and wind threat being maintained this evening. Bulk of morning CAM and machine-learning guidance are insistent on diminishing convective intensity towards 00Z, despite strengthening of the south-southwesterly low-level jet. Surface-based instability should eventually become pinched off in the Mid-South through eastern MS after sunset. This setup appears likely to yield a decreasing, but still a persistent low probability wind/brief tornado threat lingering tonight. ....Southeast KS... As the shortwave trough moves east across KS, a small corridor of opportunity for surface heating and steepening low-level lapse rates is possible near and east-southeast of the associated surface cyclone, beneath the mid-level dry slot. In the wake of morning rainfall, there may be scant MLCAPE approaching 250 J/kg. This could be barely adequate for a low-topped supercell with small to marginally severe hail and a brief weak tornado possible. ...Grams/Flournoy/Gleason.. 01/18/2023 $$ = = = 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) .