SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Mon Mar 27 2023 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR SOUTHERN GEORGIA INTO SOUTHERN SOUTH CAROLINA... ...SUMMARY... Isolated to widely scattered severe thunderstorms are possible across Georgia into southern South Carolina. Large hail and damaging gusts are the primary risks. ...Synopsis... A largely zonal upper-air pattern will extend from northern Mexico east to the Southeast states, which will be located latitudinally south of a couple of disturbances rotating through cyclonic flow over the central High Plains and Great Lakes. In the low levels, a weak surface low will develop east from the central Appalachians into the western Atlantic, while an attendant cold front pushes southward into the Southeast and central Gulf Coast/TX by Monday night. ...Southeast... Showers and thunderstorms will likely be ongoing across the Carolinas in association with a 50-kt southwesterly LLJ centered over NC at daybreak. An isolated risk for strong to locally severe thunderstorms may continue into the mid morning in the coastal Carolinas where deep-layer shear and an adequately moist/unstable airmass are forecast. Trailing outflow will likely be draped across SC in wake of this early day activity and may serve as a focus for additional storm development during the midday/afternoon. It is unclear in the placement of the boundary and whether appreciable destabilization will foster stronger storm development. Farther south into GA/AL/FL vicinity, a more pristine and unstable airmass will likely destabilize during the day as strong heating results in moderate buoyancy (1000-1500 J/kg MLCAPE). Low-level flow will weaken during the day but strong mid to high-level flow will persist. Isolated to scattered thunderstorms are forecast with organized storms evolving from the more vigorous updrafts. This activity will likely diminish by early evening. ...Southeast TX into LA... The western extension of the composite boundary will slowly sag southward into the northwest Gulf Coast region during the day. A relatively moist boundary layer near/south of the boundary and diurnal heating will result in 1000-2000 J/kg MUCAPE amidst 40-50 kt effective shear. Models continue to show at least isolated to widely scattered storms developing near or north of the boundary, mainly Monday night. Isolated large hail appears to be the primary risk. ..Smith/Weinman.. 03/27/2023
