Subj : DAY1 3/5 Risk Area Posted To : All From : Mike Powell Date : Thu May 22 2025 16:00:00 ACUS01 KWNS 221958 SWODY1 SPC AC 221957 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Thu May 22 2025 Valid 222000Z - 231200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PARTS OF NORTHWEST/NORTH TEXAS... ....SUMMARY... Severe storms are expected through the afternoon and evening across the southern Plains, especially within the Low Rolling Plains into parts of North Texas. Large hail and damaging winds are the primary hazards, with a few instances of 2+ inch diameter hail possible. ....20Z Update... The cluster of supercells that move through south-central Oklahoma and North Texas earlier have diminished in intensity. In their wake an outflow boundary has drifted southwestward into Northwest Texas and parts of the Low Rolling Plains. Here, thunderstorms have recently developed. Large buoyancy and moderate effective shear will continue to support large/very large hail with the strongest storms. Additional towering cumulus are developing in the South Plains along the surface trough/dryline. This activity should intensify this afternoon and tend to move east/southeast along the outflow boundary. Large hail and severe gusts will be possible. Strong mixing has been noted in central Texas where dewpoints have fallen into the low 50s F in some places. As this air moves toward convection farther north, storms may have some tendency to become more outflow dominant. Should a more organized cluster/MCS develop, wind gusts of 75+ mph would be possible. ...Wendt.. 05/22/2025 ..PREV DISCUSSION... /ISSUED 1139 AM CDT Thu May 22 2025/ ....Southern Plains including southern OK/northern Texas... Initially elevated, scattered, upscale-growing storms have evolved this morning across south-central Oklahoma. These storms will likely persist south-southeastward along the baroclinic gradient, potentially becoming increasingly surface based this afternoon. Additional southwest-peripheral development is also anticipated generally near the Red River as outflow/differential heating interfaces with the synoptic boundary with an aggressively destabilizing boundary layer, with upwards of 2500-3000+ J/kg MLCAPE plausible across far southwest Oklahoma into a broader part of nearby north Texas. Wind profiles will support supercells with the initial/renewed development, with clusters otherwise persisting/evolving with the ongoing Red River-vicinity storms and with anticipated additional development later today across southwest Oklahoma into/across the Low Rolling Plains of Texas. Very large hail is possible along with damaging wind potential, and some tornado risk may exist as well, although low-level shear/SRH will tend to remain modest overall. ....Southern/Eastern Florida... Seasonally cool 500-mb temperatures (-8 to -10 deg C) and moderately steep mid-level lapse rates are forecast equatorward of a large-scale eastern U.S. upper trough over the East. Deep westerly flow favors an east coast sea breeze, and this should be where convection focuses as temperatures warm through the upper 80s and lower 90s. Localized severe gusts and large hail are the primary threats with this diurnally maximized convection. ....Coastal Mid-Atlantic States... Sufficient buoyancy coincident with moderately strong wind profiles may support isolated severe low-topped storms this afternoon through around sunset in vicinity of a secondary frontal zone/triple point. ....Central High Plains... The eastward-migrating mid-level trough over the northern Rockies will favor southeasterly low-level upslope flow into the central High Plains. Modest moisture coupled with strong heating will yield 250-750 J/kg SBCAPE by mid-afternoon east of the Front Range. While storms should remain relatively isolated, elongated straight-line hodographs will support east-southeastward moving storms within an environment featuring steep 700-500 mb lapse rates (8 deg C/km). Isolated large hail and severe-caliber wind gusts will be possible. ....Northern Idaho/southwest Montana/northwest Wyoming... Some stronger to locally severe low-topped storms may occur later today within a modestly moist/unstable environment ahead of the amplifying shortwave trough over the Pacific Northwest and northern Intermountain region. $$ --- SBBSecho 3.20-Linux * Origin: ILink: CCO - capitolcityonline.net (454:3/105) .