SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0217 PM CDT Sat Oct 18 2025 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are unlikely Monday. ...Synopsis... An upper trough over the Mid-Atlantic will lift northeast across New England on Monday. Further west, another upper trough over the Rockies will develop east across the Plains to the MS Valley. Surface high pressure will be centered over the Southeast behind a prior cold frontal passage. Surface cyclogenesis is forecast across the Upper Midwest/Great Lakes vicinity with the approach of the upper trough. This will result in some increased south/southwesterly low-level flow ahead of a surface cold front sweeping southeast across the Plains to the Upper Midwest, but Gulf moisture return will remain scant. This will preclude much destabilization, but cooling aloft may be sufficient for isolated lightning flashes across parts of the Upper Midwest/Great Lakes. Additional thunderstorms are possible across New England as a surface low occludes/weakens and lifts northeast into Quebec. Low-topped convection within the warm conveyor ahead of a surface front may produce isolated lightning flashes through the daytime. The surface front will arc southwest offshore from the Mid-Atlantic/Southeast coast into northern/central FL. Isolated thunderstorms will be possible across the southern FL Peninsula amid moist/weakly unstable boundary-layer. Weak vertical shear and drying aloft will preclude severe potential. ..Leitman.. 10/18/2025
