SPC Jan 5, 2025 0600 UTC Day 1 Convective Outlook
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1144 PM CST Sat Jan 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE LOWER MISSISSIPPI VALLEY... ...SUMMARY... Strong/severe thunderstorms are expected this afternoon and evening from the Sabine River Valley into the Mid-South and lower Mississippi Valley. Severe wind gusts, tornadoes and hail will be the primary threats. ...Sabine River Valley to central Gulf States... Late-evening water-vapor imagery depicts a well-defined short-wave trough advancing east across CO/NM. This feature is forecast to strengthen as it progresses into eastern KS/OK, with a closed low expected to form as deepens. By 18z, the 500mb low should be over southeastern KS with subsequent movement into southern IL by the end of the period. This deepening low will be reflected at the surface by a sharp cold front that will extend from eastern OK into central TX at sunrise. The boundary will surge east during the day serving as the primary focus for organized convection. Early in the period, elevated convection is expected along a corridor of strong warm advection from eastern KS into western TN. Intense LLJ will be focused across the lower MS Valley through 18z, then shift east, extending across northern MS into southern KY by early evening. Boundary-layer moistening is expected to be aided by LLJ, with gradual destabilization forecast ahead of the front, especially across the lower MS Valley. Latest data does, however, maintain a cooler, stable boundary layer across much of TN where poor low-level trajectories will inhibit destabilization. Latest thinking is the greatest potential for boundary-layer destabilization will be across east TX/LA into portions of MS. Given the strong, dynamic short wave and intense mid-level height falls, a forced line of convection should develop along the cold front, possibly as early as late morning. Scattered convection may initiate across the warm sector over eastern OK shortly after 12z, then gradually expand in areal coverage with a broken squall line, or QLCS, likely by 18-20z from northern AR-northwest LA-southeast TX. Strong shear favors organized squall line, and embedded supercells. Additionally, if adequate warm-sector destabilization occurs, isolated supercells may develop ahead of the squall line. Severe wind gusts and tornadoes are the greatest concern, though some risk for marginally severe hail is also possible. Organized QLCS should propagate across the lower MS Valley into western AL during the evening where it will encounter a more stable air mass. Severe probabilities are notably lower across this lower buoyancy environment. ..Darrow/Wendt.. 01/05/2025 Read more
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1144 PM CST Sat Jan 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE LOWER MISSISSIPPI VALLEY... ...SUMMARY... Strong/severe thunderstorms are expected this afternoon and evening from the Sabine River Valley into the Mid-South and lower Mississippi Valley. Severe wind gusts, tornadoes and hail will be the primary threats. ...Sabine River Valley to central Gulf States... Late-evening water-vapor imagery depicts a well-defined short-wave trough advancing east across CO/NM. This feature is forecast to strengthen as it progresses into eastern KS/OK, with a closed low expected to form as deepens. By 18z, the 500mb low should be over southeastern KS with subsequent movement into southern IL by the end of the period. This deepening low will be reflected at the surface by a sharp cold front that will extend from eastern OK into central TX at sunrise. The boundary will surge east during the day serving as the primary focus for organized convection. Early in the period, elevated convection is expected along a corridor of strong warm advection from eastern KS into western TN. Intense LLJ will be focused across the lower MS Valley through 18z, then shift east, extending across northern MS into southern KY by early evening. Boundary-layer moistening is expected to be aided by LLJ, with gradual destabilization forecast ahead of the front, especially across the lower MS Valley. Latest data does, however, maintain a cooler, stable boundary layer across much of TN where poor low-level trajectories will inhibit destabilization. Latest thinking is the greatest potential for boundary-layer destabilization will be across east TX/LA into portions of MS. Given the strong, dynamic short wave and intense mid-level height falls, a forced line of convection should develop along the cold front, possibly as early as late morning. Scattered convection may initiate across the warm sector over eastern OK shortly after 12z, then gradually expand in areal coverage with a broken squall line, or QLCS, likely by 18-20z from northern AR-northwest LA-southeast TX. Strong shear favors organized squall line, and embedded supercells. Additionally, if adequate warm-sector destabilization occurs, isolated supercells may develop ahead of the squall line. Severe wind gusts and tornadoes are the greatest concern, though some risk for marginally severe hail is also possible. Organized QLCS should propagate across the lower MS Valley into western AL during the evening where it will encounter a more stable air mass. Severe probabilities are notably lower across this lower buoyancy environment. ..Darrow/Wendt.. 01/05/2025 Read more