Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue May 23 2023 12:42:45 ACUS01 KWNS 231242 SWODY1 SPC AC 231241 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 AM CDT Tue May 23 2023 Valid 231300Z - 241200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FROM THE SOUTH PLAINS INTO CENTRAL TX... ....SUMMARY... Isolated very large hail and damaging gusts will be possible this afternoon/evening from South Plains into central Texas. Additional strong to severe thunderstorms will be possible across Florida and the northern Great Basin. ....South Plains into central TX this afternoon/evening... Overnight convection dissipated early this morning over central TX, with only subtle hints of lingering convective outflow. The surface pattern today will consolidate into a loose baroclinic zone from northwest TX to the South Plains, southeast of a weak lee cyclone near the TX/NM border. Aloft, a series of weak perturbations will crest the ridge over NM and move southeastward toward the TX Panhandle by this evening. Surface heating and convergence/ascent along the baroclinic zone will support thunderstorm development by mid afternoon in a loose northwest-southeast band near the front, and storms will subsequently move southeastward through late evening. Midlevel lapse rates will be a little steeper today (near 8 C/km) compared to yesterday, and low-level moisture will be the same or slightly greater (58-64 F dewpoints). MLCAPE is expected to reach 2000-3000 J/kg by mid-late afternoon along the front with minimal convective inhibition. Vertical shear will be sufficient for supercells given 25-30 kt midlevel westerly flow atop low-level east-southeasterly flow, with effective bulk shear of 30-40 kt and relatively straight hodographs. The initial, more discrete supercells will be capable of producing isolated very large hail of 2 to 3 inches in diameter, while the threat for damaging winds of 60-75 mph will increase as convection grows upscale into one or more clusters. Any tornado threat will rely on favorable storm interactions, and/or locally curved hodographs close to the front this evening, at the same time upscale growth into clusters is probable. ....FL this afternoon... Similar to yesterday, a weak midlevel trough persists over MS/AL/GA, with a diffuse surface front across north FL. Surface heating will drive local sea breeze circulations south of the front, with storm formation expected from the FL Panhandle into the peninsula by early-mid afternoon. Moderate buoyancy and effective bulk shear of 25-30 kt will favor a mix of semi-organized multicells and some low-end supercells. The strongest storms will be capable of producing isolated damaging downburst winds of 50-60 mph, while steeper lapse rates aloft (in the hail growth zone) compared to yesterday may support isolated, marginally severe hail. ....Northeast NV to southeast ID this afternoon/evening... A midlevel low will form over OR, and heights will rise over the northern Plains, allowing flow to back to south-southwesterly from NV into ID. On the east edge of the stronger flow with the OR low, surface heating will result in steep low-level lapse rates and SBCAPE of 500-1000 J/kg this afternoon from northeast NV into southeast ID. Scattered multicell clusters are expected in this zone, with the potential for isolated strong-severe outflow gusts of 50-60 mph given the moderate buoyancy, effective bulk shear near 25 kt, and inverted-V profiles with DCAPE approaching 1000 J/kg. ...Thompson/Broyles.. 05/23/2023 $$ = = = 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) .