SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1134 AM CST Sat Jan 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS NORTHEASTERN LOUISIANA...FAR SOUTHEASTERN ARKANSAS...AND INTO WESTERN MISSISSIPPI... ...SUMMARY... Strong/severe thunderstorms are expected Sunday afternoon and evening from the Sabine River Valley into the lower to mid Mississippi Valley and central Gulf Coast states. Severe wind gusts, tornadoes and hail will be the primary threats. ...Synopsis... A mid-level closed low -- initially over the western Kansas vicinity -- is progged to advance steadily eastward Sunday, reaching the Mid-Mississippi Valley area by early Monday. Strong/cyclonic flow aloft surrounding this system will shift into/across the Middle and Lower Mississippi/Lower Ohio/Tennessee Valleys. At the surface, a gradually strengthening surface low will shift from the central/eastern Oklahoma vicinity Sunday morning, to the Memphis vicinity during the early evening, and eastward into eastern Tennessee overnight. Ahead of the low, a warm front will shift northward into the Tennessee Valley with time, while a cold front sweeps eastward out of eastern Texas through the afternoon, into the Delta region through early evening, and across the central Gulf Coast states through the end of the period. ...East Texas eastward to Mississippi... As a surface low shifts eastward out of Oklahoma and into Arkansas during the day, southerly low-level warm-sector flow -- and associated warm/moist advection -- will contribute to gradual/weak destabilization ahead of the advancing cold front. By early afternoon, thunderstorms are forecast to develop near -- and perhaps just ahead of -- the cold front, from central Arkansas south-southwestward into southeastern Texas, as the airmass modestly destabilizes. Very strong shear (flow veering and strengthening with height) will support storm organization, with the strongest storms likely acquiring rotation -- both within the organizing band of storms, as well as with any cellular, warm-advection-driven convection evolving ahead of the front. Damaging wind gusts are expected, along with a few tornadoes, with risk likely maximized from northern and central Louisiana eastward across the Delta region to western Mississippi from mid afternoon through mid evening. The convection will continue into the overnight hours, as the cold front shifts across central Gulf Coast states. Diminishing instability suggests a gradual decline in overall severe potential overnight. Still, locally damaging gusts and a tornado or two will likely remain possible well into the overnight hours. ..Goss.. 01/04/2025