SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0648 PM CST Thu Feb 16 2023 Valid 170100Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL GULF STATES INTO PORTIONS OF THE TENNESSEE VALLEY... ...SUMMARY... Widely scattered strong/severe thunderstorms are expected to continue from the central Gulf Coast states northward into portions of the Tennessee Valley. Isolated tornadoes are most likely over eastern Mississippi and Alabama. ...01z Update... Positive-tilt upper trough currently extends from the upper Great Lakes, southwest into the southern High Plains. Primary speed max associated with this feature is translating across the Midwest where 500mb speeds are approaching 130kt over northern IL early this evening. In response, weak surface low has migrated northeast along the boundary into western OH and the downstream warm front is oriented along the south shore of Lake Erie. While a few storms may yet develop across the OH Valley ahead of the cold front, weak buoyancy should limit overall severe threat to locally damaging winds where robust convection is able to evolve. Of potentially more significance, an elongated corridor of convection extends from eastern KY, southwest across northern AL into southeast LA. Numerous line segments with embedded supercells are noted along this zone, but purely discrete supercells are struggling to organize across the warm sector. Much of this activity is organized, but has not produced appreciable severe over the last few hours, despite the strong wind fields and modest instability. 00z sounding from LIX exhibited substantial buoyancy with around 2000 J/kg MUCAPE and 65kt surface-6km bulk shear. BMX was notably less unstable with poor lapse rates. Given the instability trends it appears the most likely corridor for organized, potentially tornadic storms is from southeast LA, across southern MS into southwest AL. Otherwise, locally damaging winds should be the main concern with convection across the Gulf States/TN Valley tonight. ..Darrow.. 02/17/2023
