Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jan 13 2025 08:59:56 ACUS48 KWNS 130859 SWOD48 SPC AC 130858 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0258 AM CST Mon Jan 13 2025 Valid 161200Z - 211200Z ....DISCUSSION... Shortwave upper ridging will move over the southern Plains vicinity on Day 4/Thu as shortwave trough develops eastward over the Southwest. While surface lee troughing will develop over the High Plains as this occurs, high pressure will persist across eastern portions of the Plains into the Southeast. This will keep Gulf moisture offshore and thunderstorm potential is low on Day 4/Thu. Forecast guidance continues to have quite a bit of spread heading into the weekend (Days 5-6/Fri-Sat). In general, the Southwest upper trough is expected migrate eastward into the southern Plains on Friday, and across the Mid-South and Southeast on Saturday. However, forecast guidance shows a fairly low-amplitude trough despite strong mid/upper southwesterly flow streaming over the Plains into the Southeast. A surface low should develop over the southern High Plains and migrate east through weekend, allowing for northward transport of Gulf moisture from east TX into the Lower MS Valley and central/eastern Gulf coast vicinity. Guidance varies quite a bit in the northward extent of moisture return. The ECMWF suite of guidance is a bit faster and further north compared to the GFS model suite. Furthermore, SPC and NSSL machine learning guidance has trended lower with severe potential compared to yesterday. While some severe potential is possible from east TX into the central Gulf coast Friday evening into Saturday, confidence remains too low to delineate unconditional Slight risk probabilities at this time. By Day 7/Sun, a cold front will move offshore the Atlantic coast and deep into the Gulf of Mexico. Strong surface high pressure and an arctic airmass will overspread much of the CONUS, bringing very cold, dry/stable conditions into early next week. ...Leitman.. 01/13/2025 = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .