Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0339 AM CST Wed Dec 18 2024 Valid 211200Z - 261200Z ...DISCUSSION... Strong surface high pressure and a dearth of boundary-layer moisture will preclude severe thunderstorm potential on Days 4-5/Sat-Sun. By Day 6/Mon, medium range forecast guidance shows a series of upper shortwave troughs shifting east from the Rockies to the MS Valley through Day 8/Wed (Christmas Day). In response, lee troughing/surface low developing is expected over parts of the southern Plains. Increasing southerly low-level flow will support modest northward transport of Gulf moisture across parts of TX into OK, and eventually the Lower MS Valley near the end of the period. While there is still quite a bit of spread with regards to intensity, location, and timing of these features, increasing thunderstorm activity is expected Day 6-8/Mon-Wed across the southern Plains vicinity. While uncertainty is high, if timing and overlap of key features comes to fruition, some severe risk could be possible over the upcoming Christmas holiday period.