Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sun May 04 2025 06:01:25 ACUS01 KWNS 040601 SWODY1 SPC AC 040559 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Sun May 04 2025 Valid 041200Z - 051200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR EAST-CENTRAL INTO SOUTHEAST NM AND A SMALL PART OF ADJACENT WEST TX... ....SUMMARY... Strong to potentially severe storms are forecast across east-central and southeast New Mexico this afternoon and evening, with a threat for large hail, isolated severe gusts, and possibly a tornado. Other strong to locally severe storms are possible from Florida northward into the Mid Atlantic and Allegheny Plateau. ....Synopsis... An amplified upper-level pattern will remain in place today across the CONUS. A deep trough will cover much of the West, as an embedded mid/upper-level cyclone moves slowly eastward across the Southwest. Farther east, a deep mid/upper-level cyclone is forecast to remain nearly stationary over parts of the OH/TN Valleys. At the surface, a cold front will continue moving across parts of the Southeast, while the Mid-Atlantic portion of the front is expected to move little through the day. A weak surface low will may persist across OH/WV/southwest PA, with other weak waves potentially developing along the front. Farther west, lee troughing will result in strengthening southeasterly low-level flow into parts of NM and west TX, accompanied by modest moisture return. ....NM into west TX... While low-level moisture will remain rather limited, dewpoints increasing through the 40s to near 50 F beneath steep midlevel lapse rates will result in MLCAPE of 500-1000 J/kg by late afternoon into the evening. Large-scale ascent downstream of the midlevel cyclone over the Southwest will aid in development of scattered to numerous thunderstorms from northern into east-central NM, with more isolated storms possible into far southeast NM and west TX. Veering wind profiles and increasing midlevel flow will provide sufficient deep-layer shear for storm organization, and development of a few supercells will be possible. Large hail and localized severe gusts will be possible. In addition, enlarging low-level hodographs and gradually improving moisture could support a tornado or two if any mature supercells can persist through late afternoon into the evening. ....Florida... A few stronger storms will be possible across parts of north FL during the morning, in the vicinity of the cold front. Depending on the evolution of any morning convection and related cloudiness, relatively cold temperatures aloft and diurnal heating will allow for moderate destabilization during the afternoon. Scattered diurnal storm development is expected, especially in the vicinity of the Atlantic sea breeze. MLCAPE of around 2000 J/kg and effective shear of 25-30 kt will support potentially organized storms capable of hail and damaging gusts. Some tornado threat could also materialize in the vicinity of the sea breeze or any other boundaries. Some uncertainty remains regarding how any morning convection and its possible persistence will affect sea-breeze-related storm development, especially with northward extent up the coast. ....Allegheny Plateau into the Carolinas... Cold temperatures aloft may support modest diurnal destabilization across parts of OH/WV/western PA. Storm development may be aided during the afternoon by one or more low-amplitude vorticity maxima rotating around the midlevel cyclone. Low-level flow is expected to remain rather weak, but modestly veering wind profiles and moderate midlevel flow could support some storm organization, if sufficient buoyancy can be realized. Hail and locally gusty winds could accompany the strongest storms. A mesoscale corridor of somewhat greater threat could evolve, depending on the magnitude of heating/destabilization. Farther south into the Carolinas and parts of the Mid Atlantic, somewhat stronger diurnal heating is expected, and MLCAPE may increase to near/above 1000 J/kg. However, storm coverage is more uncertain, with a notable midlevel dry slot and only weak to modest large-scale ascent expected with southward extent. Any storms that can mature within this environment could become modestly organized with a threat of isolated hail and damaging gusts. ....Eastern ID into southwest MT... Scattered storm development is possible this afternoon and evening from eastern ID into southwest MT, within an environment characterized by cold temperatures aloft and steep lapse rates. Deep-layer shear will be relatively modest, but a couple stronger storms with small hail and gusty winds will be possible. If trends end up supporting the more aggressive guidance regarding destabilization in this area, then severe probabilities may eventually be needed. ...Dean/Moore.. 05/04/2025 $$ = = = 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) .