Subj : DAY3SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Jan 21 2023 08:08:41 ACUS03 KWNS 210808 SWODY3 SPC AC 210807 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 AM CST Sat Jan 21 2023 Valid 231200Z - 241200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... The risk for severe thunderstorms currently appears negligible across the U.S. Monday through Monday night. ....Synopsis... Models indicate further amplification of the mid/upper flow across the mid-latitude Pacific during this period. This is likely to include building of the persistent large-scale ridging offshore of the North American coast, through much of the remainder of the northeastern Pacific and southeastern Alaska/British Columbia coastal areas. An initially prominent embedded high over the southern mid-latitudes is forecast to weaken, with a new high gradually beginning to form in the northern mid-latitudes. As this occurs, it appears that a vigorous short wave trough and embedded mid-level low, within a southern branch of split downstream westerlies, will gradually turn eastward into/across the southern Rockies vicinity. After bottoming out near the Southwestern international border area, and interacting with a branch of westerlies emanating from the subtropical eastern Pacific, spread among the various models increases with regard to the eastward progression of this perturbation by late Monday night. In the wake of a significant preceding short wave trough and associated surface cyclone progressing away from the Atlantic Seaboard, a trailing frontal zone is forecast to advance through much of the Florida Peninsula and the Gulf of Mexico. However, in response to deepening surface troughing to the lee of the southern Rockies through the lower Rio Grande Valley vicinity, the front may redevelop back to the north, across the northwestern Gulf of Mexico into portions of southern Texas by late Monday night. An elevated return flow of Gulf moisture into parts of central and southeast Texas may contribute to increasing convection and embedded thunderstorms Monday night, when destabilization beneath strong mid-level cooling may also contribute to a risk for thunderstorm activity across the High Plains of New Mexico into west Texas. Although mid-level lapse rates may be initially steep, as shear increases through the convective layer, the extent to which destabilization may support a risk for severe hail remains unclear. Once spread within/among the various model output begins to decrease, it is possible that low severe weather probabilities may be needed in later outlooks for this period. For now, though, the risk for severe thunderstorms still appears less than 5 percent. ...Kerr.. 01/21/2023 $$ = = = 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) .