
Day 4-8 Outlook

Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0332 AM CDT Thu Mar 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... ...Day 4/Sun - Eastern U.S.... A large-scale upper trough near the MS Valley Sunday morning will develop east to the Appalachians by early Monday. Strong deep-layer south/southwesterly flow on the eastern side of the upper trough will overspread much of the eastern U.S. Convection will likely be ongoing Sunday morning from the Upper OH Valley into GA and northern FL. This activity will move into a moist airmass, characterized by 60s F dewpoints from north FL toward the Chesapeake Bay vicinity (50s F dewpoints further north into PA/NJ). Instability will be greatest where deeper boundary layer moisture is forecast, but given intense deep-layer flow, organized convection is expected with even very modest instability. While linear convection producing damaging gusts will be the main hazard for much of the region, tornado potential will exist where sufficient boundary layer moisture exists, most likely from the Carolinas southward. ...Days 6-7/Tue-Wed - OK/KS into the MS/OH/TN Valleys... Another large-scale upper trough is forecast to move across the West and into the Plains on Tuesday into early Wednesday, and then into the Midwest by Thursday. This will bring some potential for severe storms. However, a prior cold frontal intrusion deep into the Gulf and surface high pressure east of the MS River in the wake of the Day 4/Sun upper trough will limit moisture return into the southern/central Plains on Tuesday. Modest moisture return is possible further southeast on Wednesday, but forecast guidance currently is unremarkable. Trends will be monitored, but the probability for any more an isolated/marginal severe appears low at this time.