Subj : DAY1 3/5 Risk Area Posted UPDATED To : All From : Mike Powell Date : Wed Apr 29 2026 20:17:30 ACUS01 KWNS 292002 SWODY1 SPC AC 292000 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Wed Apr 29 2026 Valid 292000Z - 301200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE EDWARDS PLATEAU INTO SOUTH-CENTRAL TEXAS... ....SUMMARY... Severe thunderstorms are forecast from parts of Texas to the Gulf Coast states today. Scattered large to very large hail and damaging winds are the primary risks, with giant hail possible in parts of south-central Texas. ....20Z Update... The primary change with this update was the addition of an Enhanced Risk for portions of the Edwards Plateau into south-central TX -- driven by a CIG2 (intensity level 2/2) hail area. The latest visible satellite imagery indicates an agitated boundary-layer cumulus field evolving east of Fort Stockton in Crockett County, where attempts at isolated convective initiation are underway. Current thinking is that continued diurnal heating of a moist air mass (lower 70s dewpoints) and upslope flow enhancements will result in isolated to widely scattered thunderstorms this afternoon into the evening. Current thinking is that storms will track/develop southeastward into a corridor of strong to extreme buoyancy -- driven by steep midlevel lapse rates (around 8.5 C/km per 12Z DRT sounding) atop the destabilizing PBL. This, combined with a long/straight hodograph (60-70 kt of effective shear) and modest forcing for ascent will favor intense discrete/splitting supercells. Given the modest forcing for ascent, it is unclear how many storms will form in this corridor, though any sustained supercells will pose a risk of very large to giant hail (3-4+ inches in diameter). ...Weinman.. 04/29/2026 ..PREV DISCUSSION... /ISSUED 1049 AM CDT Wed Apr 29 2026/ ....Texas into the Lower Mississippi Valley/Southeast... Satellite imagery late this morning indicates high momentum quasi-zonal flow from TX eastward across the central Gulf Coast. An upstream perturbation over Chihuahua is forecast to move quickly east today reaching central TX late this afternoon. Isolated to scattered thunderstorms are forecast to increase in coverage/intensity mainly along/near a surface front draped from west-central TX to southern AR. A moisture-rich airmass featuring lower 70s deg F surface dewpoints south of the front, coupled with a plume of 8 deg C/km 700-500 mb lapse rates and some diurnal heating, will contribute to 2000-4000 J/kg of MLCAPE decreasing with east extent. A few initial thunderstorms clusters north of the surface front over TX are expected to gradually intensify through early afternoon. The moderate to very unstable airmass will combine with elongated/nearly straight hodographs to support supercell development with the stronger updrafts and an associated risk for large to very large hail (1 to 3 inches in diameter). Have extended the 15-percent hail and CIG1 hail delineation farther east into northeast TX and western LA. For short-term forecast details, please refer to MCD #615. Eventually upscale growth into one or more clusters is expected to evolve across LA into the central Gulf Coast states later this afternoon. Damaging gusts and an isolated risk for large hail will be the primary hazards with the stronger storms. Farther west, isolated to widely scattered intense storm development is forecast across the Edwards Plateau this afternoon. This activity may eventually focus closer to the Rio Grande later this evening with a large to very large hail threat persisting well after dark. ....Upper OH Valley into the Mid-Atlantic/North Carolina... Within large-scale upper troughing over the Great Lakes/Midwest, an embedded mid-level shortwave trough will move northeastward across the Mid-Atlantic this afternoon/evening in tandem with an eastward-moving surface cold front. Only modest boundary layer moisture is present across the region, with surface dewpoints generally in the 50s. Forecast soundings over western PA show some low-level hodograph curvature within a moist environment. Main uncertainty across the upper OH Valley is the magnitude of destabilization in this area given ongoing scattered showers and widespread cloud cover. Nonetheless, a couple of stronger storms could yield an isolated risk for wind damage and perhaps a brief tornado later this afternoon, especially near/southeast of a weak surface low. Farther south, isolated wind/hail will be possible with the stronger thunderstorms through the late afternoon/early evening. $$ --- ScorpioWeb v0.32a (Linux/x86_64) * Origin: ILink: Project Scorpio TEST (454:1/105.6) .