Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Sep 29 2023 17:18:45 ACUS02 KWNS 291718 SWODY2 SPC AC 291716 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1216 PM CDT Fri Sep 29 2023 Valid 301200Z - 011200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Severe storms appear unlikely on Saturday. ....Synopsis and Discussion... Overall upper pattern is expected to undergo significant amplification throughout the day Saturday as troughing deepens over the western CONUS and ridging builds across the central and eastern CONUS. Cold mid-level temperatures and strong forcing for ascent accompanying the upper trough will support the development of isolated thunderstorms from central CA into the Great Basin through the period. Surface lee troughing is expected to sharpen throughout the period in response to the deepening western CONUS upper troughing and persistent southerly/southwesterly flow across the Rockies. Lower surface pressures will contribute to a broad area of return flow across the Plains. Even so, strong boundary-layer mixing is anticipated, with afternoon/evening dewpoints in the upper 50s across the majority of the Plains. The only exception is in the vicinity of a warm front extended across the Dakotas into Upper MS Valley where low to mid 60s dewpoints are possible. Anticipated mixing coupled with warm temperatures aloft should preclude afternoon/evening thunderstorm development across the majority of the Plains. Some isolated to scattered storm development is possible over the southern Rockies, with storms then moving into the southern High Plains. Weak shear should limit overall storm duration and strength. Warm-air advection thunderstorms are possible early in the period over the Upper MS Valley, but these should weaken throughout the morning as the low-level jet weakens. Vertical shear will be moderate, and a few instances of hail are possible. Another round of storms is anticipated Saturday night across the MN Arrowhead/ northern WI/upper MI vicinity as the low-level jet nocturnally strengthens once again. Moderate elevated instability is expected but shear will be relatively weak. Sporadically strong storms, particularly with any initial, more cellular development, could potentially produce localized hail. At this time, the threat appears too conditional to introduce severe probabilities. ...Mosier.. 09/29/2023 $$ = = = 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) .