Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Feb 27 2023 01:00:57 ACUS01 KWNS 270100 SWODY1 SPC AC 270059 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0659 PM CST Sun Feb 26 2023 Valid 270100Z - 271200Z ....THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF WEST-CENTRAL INTO NORTHEASTERN OKLAHOMA... ....SUMMARY... A serial derecho event remains likely across portions of the southern Plains into tonight. Widespread damaging winds and embedded swaths of significant severe gusts from 80-110 mph may still occur, mainly over parts of Oklahoma this evening. Embedded tornadoes are also possible, a couple of which may be strong, especially over southwest Oklahoma. ....Synopsis... A 990 mb surface low over southwestern KS will continue to deepen as a negatively tilted mid-level trough with a 110+ kt jet streak ejects into the southern Plains tonight. Ongoing strong to severe thunderstorms immediately ahead of a Pacific cold front will continue to increase in coverage and intensity as they progress rapidly eastward across central KS/northern TX into southwest MO this evening. Though buoyancy may be modest, impressive shear profiles and deep-layer ascent will compensate to support a potentially widespread severe threat. ....Southern Plains this evening into tonight... The aforementioned band of convection across the southern High Plains continues to intensify, with a mix of linear segments and semi-discrete supercells noted across the eastern TX Panhandle into far western OK and southwest KS. Multiple convective gusts (some around hurricane force) have already been observed, along with a couple of possible brief tornadoes in southwestern KS. 23Z mesoanalysis shows a 50+ kt low-level jet currently overspreading western OK ahead of the ongoing storms, contributing to both an influx of moisture and impressive deep-layer/low-level shear values. Though the boundary layer is relatively cool across portions of northern TX into central KS, continued advection of 60+ F surface dewpoints beneath 8+ C/km mid-level lapse rates will foster 500-1000 J/kg MLCAPE. Coincident with the buoyancy axis are strong, veering vertical wind profiles, with 23Z RAP forecast soundings and regional VADs showing very large and curved hodographs and widespread 500+ m2/s2 0-3 km SRH. As such, any supercells that can ingest surface-based buoyant parcels could become tornadic, with a couple of strong tornadoes possible. The best chance for strong tornadoes would be in western Oklahoma, where low-level moisture is richest. As the evening progresses, storms should rapidly merge/grow upscale into a QLCS, potentially supporting a serial derecho event. Given 75+ kt flow below 1000 m AGL, mechanical downward momentum transport should support numerous to potentially widespread severe wind gusts through the evening from central KS into central and southern OK. The latest high resolution guidance consensus continues to depict LEWPs/possible meso-gamma vortices embedded within the QLCS, especially across west-central OK into north-central OK in the 02-04Z (8-10 PM CST) time frame. In addition to embedded QLCS tornadoes, the combination of downward momentum transport and channeled flow associated with LEWPs/meso-gamma vortices may support several significant-severe wind gusts, a few of which may exceed 85 mph. Though the QLCS may peak in intensity before crossing the I-35 corridor and outpace the surface-based warm sector, intense low-level wind profiles/dynamic forcing should continue to support a severe wind threat into northeast OK/southwest MO through tonight. ...Squitieri.. 02/27/2023 $$ = = = 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) .