Subj : DAY48SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Nov 16 2023 10:02:20 ACUS48 KWNS 161002 SWOD48 SPC AC 161000 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ....DISCUSSION... ....Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ....Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. ...Broyles.. 11/16/2023 = = = 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) .