SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Thu May 29 2025 Valid 291630Z - 301200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE TEXAS SOUTH PLAINS INTO THE TEXAS BIG COUNTRY... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE COASTAL PLAIN OF GEORGIA AND SOUTH CAROLINA... ...SUMMARY... Large to very large hail, significant severe gusts, and a couple of tornadoes will be a concern with thunderstorms this afternoon and evening from the Texas-New Mexico border eastward into central Texas. Thunderstorms producing scattered damaging winds are possible this afternoon across parts of the Southeast. ...Southern Plains... Visible satellite imagery indicates strong heating will occur south of a cold front currently draped from east-central NM into the southern portion of the TX Panhandle/South Plains. Relatively moist low-level easterly flow with 60s deg F surface dewpoints and steep mid-level lapse rates, will support MLCAPE up to 2500-3000 J/kg by mid/late afternoon and 35-45 kt of deep-layer shear. Even though large-scale forcing associated with an upper trough over the Midwest and central Plains will remain modest with southward extent into the southern High Plains, scattered thunderstorm development is forecast by mid-late afternoon near the front and across southeast NM, with increasing coverage and clustering possible this evening. Models shows initially supercells capable of large to very large hail and perhaps some tornado risk early in the convective life cycle across parts of eastern NM into portions of the TX South Plains. The aforementioned upscale growth/clustering is expected and depicted in several recent CAMs, suggestive of a corridor of severe gusts (perhaps locally in the 70-85 mph range) mainly this evening. Farther east, most guidance depicts more isolated coverage of thunderstorms near the front from southern OK into north TX. However, moderate to strong instability and sufficient deep-layer shear will support a conditional risk of large hail and damaging wind with any sustained convection in this region. Isolated strong to severe thunderstorms will also be possible from the Raton Mesa vicinity southward across eastern NM, within a weakly unstable but favorably sheared environment. The strongest cores may pose a threat of isolated hail and severe gusts during the afternoon and early evening. ...Southeast... Isolated strong to severe thunderstorms this morning along the Gulf Coast will continue east across adjacent portions of southern AL/FL Panhandle into southern GA. This activity is immediately ahead of an eastward-migrating shortwave trough over the northern Gulf Coast. Extensive cloud debris and some convective overturning this morning will act to limit the overall severe threat across the FL Panhandle/southern AL. Farther east and northeast, stronger destabilization has occurred through midday with temperatures rising into the 80s/lower 90s deg F and dewpoints in the low-mid 70s. MLCAPE increasing to around 1500-2000 J/kg is forecast over the coastal plain where stronger heating has occurred already this morning. Strong to severe convection may either persist from the ongoing morning activity, or initiate within the weakly capped environment across parts of GA into SC. Low-level flow will likely remain rather weak, but some strengthening of westerly mid-level winds should support one or more loosely organized clusters capable of producing scattered damaging winds and perhaps isolated hail. ...Ozarks into the Mid-South... Some low-level moistening is expected through the day from parts of northern AR/southern MO into the Mid-South, in association with a approaching mid/upper-level trough and developing weak surface cyclone. Relatively modest heating and weak lapse rates aloft may tend to limit buoyancy, but ascent attendant to the approaching shortwave trough may support scattered thunderstorm development along/ahead of a front from late afternoon into the evening. Have expanded low-severe probabilities farther east into south-central KY and Middle TN where recent guidance shows sufficient destabilization may occur late tonight. The strengthening wind profiles during this timeframe ahead of the mid-level disturbance may support a conditional risk for a few supercells capable of all-severe hazards. ..Smith/Karstens.. 05/29/2025