Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed May 21 2025 16:34:04 ACUS01 KWNS 211632 SWODY1 SPC AC 211631 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Wed May 21 2025 Valid 211630Z - 221200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN NORTH CAROLINA...SOUTHERN GEORGIA/NORTHERN FLORIDA...AND THE OZARKS... ....SUMMARY... The most likely areas for severe storms are across parts of far eastern North Carolina, the upper Ohio River Valley and parts of the Southeast this afternoon, in addition to the Ozarks this evening. ....Eastern North Carolina/southern Virginia... In the wake of early morning convection, air mass recovery/destabilization will occur today in vicinity of the eastward-transitioning surface wave and in vicinity of the roughly west/east-oriented surface boundary located near/south of the Virginia/North Carolina border. Drying westerly low-level trajectories will exist to the south of the front and behind the surface wave, with severe-storm favorable ingredients/potential development tending to focus across far northeast North Carolina where moderate buoyancy will be maximized with strong westerlies aloft (40+ kt effective shear). While severe storm coverage/likelihood may not be as high as previously thought, some potential for large hail, damaging wind gusts and possibly a tornado will still exist on an isolated basis. ....Ozarks/Mid-South... While rich boundary-layer moisture will remain confined across south Texas and Louisiana, a strengthening low-level baroclinic zone will focus near the Kansas/Oklahoma border east-southeast into the Mid-South. Guidance is rather consistent in developing at least elevated convection to the cool side of this zone by evening. This will be coincident with an intensifying mid-level speed max. Forecast soundings depict potentially very strong mid to upper-level speed shear within the slightly north of west flow regime. Coupled with steep mid-level lapse rates, this setup could yield a few elevated supercells capable of large hail and perhaps locally damaging winds. ....Central Plains... A mid-level vorticity lobe initially over Wyoming this morning will dig east-southeastward into the lower Missouri Valley by early evening amidst west-northwesterly flow aloft. Heating will result in very steep 0-3 km lapse rates by mid afternoon with several hundred J/kg SBCAPE. Elongated hodographs will support quick-moving cells capable of an isolated risk for severe wind gusts during the late afternoon through around sunset (roughly 20-01z). ....Upper Ohio Valley including PA/OH/WV border region... A corridor of modest boundary-layer heating is expected ahead of the primary surface cyclone drifting across northern Ohio toward Lake Erie. Coupled with cooling mid-level temperatures, weak surface-based buoyancy is expected by midday into the afternoon. Deep-layer shear will not be strong given proximity to the mid-level trough, but should be adequate for weak/transient mid-level rotation. With numerous thunderstorms expected, small to marginally severe hail and isolated damaging winds are anticipated. A brief tornado or two is also possible with storms near the warm front, before convection weakens as it moves east-northeastward into less-buoyant surface conditions. ....North Florida and southern Georgia... Along the southeastward-moving cold front, moderate buoyancy is expected ahead of the front. A veered low-level wind profile will limit effective bulk shear, but scattered thunderstorms could yield multicells and perhaps a transient supercell. Isolated damaging winds and marginally severe hail are possible with the stronger storms. For additional short-term details, see Mesoscale Discussion 920. ....Far southern Louisiana/far southern Mississippi... Sufficient residual elevated buoyancy in the immediate post-frontal environment may allow for some storms to produce hail to near severe levels, mostly over just the next few hours this afternoon and on a very isolated basis. ....Deep South Texas... A very moist and unstable air mass (2000-4000 J/kg MLCAPE later today) exists across the region, aside from some higher cloud cover spreading into the region via a slowly approaching and weakening convective complex south of the international border. Additional convection will likely develop in adjacent Mexico over the higher terrain this afternoon, and some of these storms may spread east across the lower Rio Grande Valley this evening. Isolated large hail and severe-caliber wind gusts may accompany these storms. ...Guyer/Jewell.. 05/21/2025 $$ = = = 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) .