1PM Day 1 Convective Outlook for Tuesday, February 3. NO SEVERE THUNDERSTORM AREAS FORECAST
SUMMARY
Severe thunderstorms are not forecast through tonight across the contiguous United States.
20z Update
Minor adjustments were made to bring the thunder line further north into Middle Tennessee to account for trends over the last couple of hours. Otherwise, the outlook remains unchanged. See previous discussion below for more information.
Synopsis
Upper pattern is expected to amplify today, largely a consequence of a deepening central/eastern CONUS upper trough. This large-scale deepening will be fostered by the progression and evolution of several shortwave troughs as they move through the western and southern periphery of the parent upper troughing. The first of these waves is currently moving southeastward through the Lower MO Valley, with continued east-southeastward/eastward motion expected to take this wave across the Mid-South, TN Valley, and central Appalachians today.
A modest warm sector precedes this lead wave, with some low-level moisture return currently noted across the TX Coastal Plains into central and east TX. Some moisture return today will continue as the shortwave progresses eastward and an associated cold front pushes southeastward across TX and the Mid-South/Lower MS Valley. However, much of the central Gulf basin remains fairly dry due to previous frontal intrusions, likely limiting the overall moisture return from the Lower MS Valley eastward across the remainder of the Southeast. This will confine the better low-level moisture return to the TX Gulf Coast and southwest LA. Warm-air advection across this modestly moist portion of the warm sector could contribute to some buoyancy. However, tempered heating and poor lapse rates will mitigate the overall magnitude of any buoyancy that does develop. Even so, occasional updrafts should still be deep enough for isolated lightning, particularly from east TX into central LA where the highest thunderstorm coverage is anticipated. Modest vertical shear will be in place, but the overall severe risk will be limited by weak buoyancy.