SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0643 AM CST Sat Nov 08 2025 Valid 081300Z - 091200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHERN GEORGIA INTO THE CAROLINAS... ...SUMMARY... Thunderstorms capable of marginally severe hail and isolated severe wind gusts will be possible this afternoon and evening across parts of northern Georgia and the Carolinas. ...Synopsis... A progressive upper pattern is expected today as a pair of shortwave troughs progress across the central and eastern CONUS. The eastern shortwave, which is currently over the Upper OH Valley, will continue quickly eastward/northeastward, moving off the Northeast coast by this afternoon. The western shortwave will dig southeastward across the northern/central Plains, reaching the Lower OH Valley by early tomorrow morning. Evolution of these shortwaves will maintain a cyclonic belt of enhanced westerlies from the central Plains through the Mid-Atlantic States throughout the period. At the surface, a weak frontal zone extends from central NY southward to just off NJ and DE before arcing back southwestward across central NC/far western SC and continuing west-southwestward across the Southeast. Northern/eastern portion of this boundary will remain progressive while the western portion stays largely in place through the afternoon. During the evening, this boundary will likely begin shifting northward as a warm front ahead of the next shortwave and its associated surface low. Thunderstorm coverage will increase during this time across eastern GA and the Carolinas. ...Northern GA and the Carolinas... As mentioned in the synopsis, northward progression of a warm front will bring increasing low-level moisture into GA and the Carolinas this evening. A weak surface low will likely move across the region as well. Much of the large-scale forcing for ascent will be displaced north and west of the region, but a combination of localized lift near the surface low and persistent warm-air advection is still expected to result in increasing thunderstorm coverage from the late afternoon through the evening. Buoyancy will be modest, tempered by poor lapse rates, but vertical shear will be strong, and the overall environment could support some more organized updrafts. A more cellular mode is favored and hail appears to be the primary severe risk, although a damaging gust or two is also possible. Additionally, given favorable low-level wind profiles, a low-probability tornado threat also exists, particularly near the surface low. However, increasing low-level stability and meager buoyancy should keep the tornado risk low. ...OH Valley... Strong forcing for ascent and cold mid-level temperatures will support an arcing band of thunderstorms over the region, beginning across central/southern IL and far western KY early Sunday morning. The stronger mid-level flow will likely be displaced south of the deeper convection and some low-level stability will be in place, but a few stronger gusts could still reach the surface. Some small hail is possible across the region as well. ..Mosier/Squitieri.. 11/08/2025
