Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CST Fri Dec 13 2024 Valid 161200Z - 211200Z ...DISCUSSION... A shortwave upper trough will traverse the Midwest and Great Lakes region on Day 4/Mon. Meanwhile, a cold front will track southeast across the southern Plains and Mid-South vicinity, extending from northern AL toward the Upper TX Coast/south-central TX by early Day 5/Tue. Southerly low-level flow ahead of the front will bring Gulf moisture across the south and east Texas into the lower MS Valley/central Gulf coast region, aiding in modest destabilization on Monday. However, stronger mid/upper level flow and large-scale ascent will remain north over the Midwest. Furthermore, deep-layer flow will mostly be parallel to the cold front. As a result, warm-advection precipitation and thunderstorms are likely from east TX into the Lower MS Valley, but severe potential appears limited. The cold front from Day 4/Mon will likely stall on Day 5/Tue across parts of the TX coast and Lower MS Valley. By late Tuesday into Day 6/Wed, another upper trough is expected to eject across the Plains into the Southeast. A sharper cold front associated with this system will move offshore the Gulf coast, with some potential for heavy rain and thunderstorms. However, given prior days' convection, poor heating/widespread cloudiness and weak instability, severe potential is not expected. Given the strong cold front intruding into the Gulf, boundary-layer moisture will become scant and severe- thunderstorm potential is expected to be low Days 7-8/Thu-Fri.