Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0308 AM CST Tue Nov 04 2025 Valid 071200Z - 121200Z ...DISCUSSION... ...D4/Friday... An area-of-interest, sufficient for a Predictability Too Low highlight, appears centered on the OH Valley to Deep South. A large-scale mid/upper trough should consist of several embedded shortwave impulses progressing east from Hudson Bay through the central to eastern CONUS. Primary surface cyclone is expected to shift from the Upper Great Lakes into QC, with a trailing cold front to its southwest undergoing frontolysis in the TN Valley/Deep South by Friday night. Modified moisture return from the southern Gulf may support moderate buoyancy over the Lower MS Valley, with a plume of weak buoyancy extending into the OH/TN Valleys ahead of the front. A belt of strong mid-level westerlies will yield favorable deep-layer shear for organized severe potential. Latest GEFS-based SPC/NSSL ML probs have trended upward with severe indications, more aggressive than yesterday's available NCAR ECENS-based guidance. Overall setup may tend to favor a more mesoscale-driven 15% area given uncertainty on timing of convective development along the southwest extent of the weakening front and the degree of destabilization where ascent is stronger to the northeast. ...D6/Sunday... Substantial amplification of the next mid/upper trough is largely progged across the central to eastern states late Saturday through Sunday. This should induce more southerly cyclogenesis across the North-Central States into the Lower Great Lakes. With the D4 wave aiding in low-level moisture return from the southern Gulf, latest guidance indicates seasonably rich dew points may be more prevalent across the eastern Gulf and South Atlantic Coasts by late weekend. This signal distinctly lacks run-to-run continuity, but should foster at least low-probability severe potential across the Southeast Coastal Plain.
