Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Feb 25 2023 10:07:45 ACUS48 KWNS 251007 SWOD48 SPC AC 251006 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0406 AM CST Sat Feb 25 2023 Valid 281200Z - 051200Z ....DISCUSSION... ....Tuesday/Day 4 and Wednesday/Day 5... A long fetch of west-southwest mid-level flow is forecast on Tuesday from the Desert Southwest to the Eastern Seaboard. A moist airmass will be in place in the Gulf Coast region but thunderstorm potential is expected to remain limited due to a lack of large-scale ascent. On Wednesday, a moist airmass is forecast to advect northward into the lower to mid Mississippi Valley. An axis of instability should develop by afternoon from east Texas into the Arklatex. Thunderstorms, and possibly a conditional isolated severe threat, may develop along and to the east-northeast of the stronger instability from the Arklatex into the Tennessee Valley. ....Thursday/Day 6 to Saturday/Day 8... A progressive upper-level trough is forecast to move across northern Mexico on Thursday. Ahead of this system, low-level moisture may return northward into parts of central and east Texas by afternoon, with a moist airmass extending eastward across much of the Gulf Coast region. Model forecasts suggest that instability could be sufficient for a severe threat from east Texas extending eastward into the central Gulf Coast states. Thunderstorms associated with wind damage, hail and possibly an isolated tornado threat, would be possible within this moist airmass from mid afternoon into the evening. On Friday, the upper-level trough is forecast to move east-northeastward across the southeastern U.S. Solutions vary on the quality of the airmass across the Gulf Coast region. The current thinking is that the most favorable airmass will be located across south and central Mississippi extending eastward into southern and central Alabama. During the day, the severe threat could become maximized within this area. Wind damage, hail and possibly a few tornadoes could occur with supercells and/or bowing line segments. The wind-damage threat could become amplified if an organized squall line can develop. For both Thursday and Friday, too much uncertainty exists concerning the quality of the moisture and timing of the upper-level trough to add a severe threat area. With more run-to-run consistency, a severe threat area may need to be added in the next outlook cycle. On Saturday, the potential for thunderstorms across the continental U.S. appears low, mainly due to the advection of a cool and dry airmass into the central and southern states. ...Broyles.. 02/25/2023 = = = 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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .