SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Oct 19 2025 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE CENTRAL APPALACHIANS INTO THE MID ATLANTIC AND SOUTHERN NEW ENGLAND...AND ALSO NEAR PARTS OF THE GULF COAST... ...SUMMARY... Isolated strong to severe storms are possible this morning from south Alabama into southwest Georgia and the Florida Panhandle. Localized wind damage will be possible later today from the central Appalachians into parts of the Mid Atlantic. Late tonight, localized wind damage and possibly a brief tornado will be possible from the northern Mid Atlantic into parts of southern New England. ...Synopsis... A deep mid/upper-level trough is forecast to take on a negative tilt as it moves eastward from the MS Valley into the Mid Atlantic and Northeast. A surface low initially over Lower MI will move north-northeastward toward Hudson Bay, with secondary low development expected in the upper Great Lakes vicinity late in the period. A cold front will surge southeastward through parts of the Southeast, Ohio Valley, and Mid Atlantic. ...South AL into the FL Panhandle and southwest GA... Strong to locally severe storms will likely be ongoing at the start of the period across parts of south AL and the western FL Panhandle. Rich boundary-layer moisture, sufficient buoyancy, and initially favorable low-level and deep-layer shear will support potential for locally damaging gusts and possibly a tornado or two. As large-scale ascent lifts away from the region with time, a general weakening trend is currently expected from late morning into the afternoon. ...Central Appalachians into the Mid Atlantic vicinity... Buoyancy will remain quite limited through most of the day along/ahead of the cold front from the central Appalachians into the Mid Atlantic. However, low/midlevel flow will be strong, with 40-50 kt in the 850-700 mb layer. A band of low-topped convection (potentially with little or no lightning) will likely develop along the eastward-moving cold front, and may become capable of producing convectively enhanced strong/damaging gusts within this strong-flow regime. Late in the period, somewhat richer low-level moisture (with dewpoints in the low 60s F) will advect inland into northern parts of the Mid Atlantic and southern New England. Buoyancy may become sufficient for somewhat deeper convection, as indicated by a modest increase in HREF calibrated thunderstorm probabilities between 06-12Z. With strong low-level flow/shear in place, locally damaging wind and possibly a brief tornado could accompany convection along the front into early Monday morning. ..Dean/Thornton.. 10/19/2025
