Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Aug 26 2025 16:59:42 ACUS02 KWNS 261659 SWODY2 SPC AC 261658 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1158 AM CDT Tue Aug 26 2025 Valid 271200Z - 281200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... The potential for severe storms appears to be low across the continental U.S. tomorrow (Wednesday), though a few stronger storms are possible across parts of the Upper Midwest and Colorado Front Range where locally gusty winds and small hail are possible. ....SD/MN/IA Vicinity... A broad upper trough will be in place from the Upper Midwest to the Northeast and Mid-Atlantic, resulting in a persistent mid/upper northwest flow regime across the region. Forecast guidance suggests a weak shortwave impulse will move across the eastern Dakotas and MN/IA during the morning/early afternoon. Meanwhile, a weak front will develop southward, extending generally west to east across eastern SD into southern MN by peak heating. Weak southerly low-level flow will promote shallow boundary layer moisture, with surface dewpoints in the upper 50s to low 60s along/ahead of the surface boundary. Midlevel lapse rates are expected to remain modest, but weak instability (around 500-1000 J/kg MLCAPE) is forecast. Some early-day showers and clouds may linger, but isolated thunderstorms will likely develop during mid to late afternoon near the surface boundary from far eastern SD into southern MN. Vertically veering wind profiles, with strengthening northwest flow through the mid/upper levels will support effective shear magnitudes in the 25-35 kt range. Forecast hodographs also appear elongated/straight. While 500 mb temperatures are forecast in the -10 to -12 C range, some warming around 700 mb is apparent in some forecast soundings. While an organized storm or two may become strong within a favorable shear parameter space, it is uncertain if robust updrafts will be maintained given marginal thermodynamics and some contamination to the environment from early-day activity. An isolated strong gust or small hail may be possible with the strongest storms for a couple hours during the late afternoon or early evening, but overall severe potential looks limited at this time. ....Central High Plains... South to southeasterly low-level flow will transport mid 50s to low 60s F dewpoints northwest across the central High Plains beneath modest upper ridging over the western U.S. Daytime heating and a developing lee-trough will provide focus for thunderstorm development by late afternoon along the CO/southeast WY Front Range. Midlevel lapse rates are forecast to remain weak, but sufficient for MLCAPE in the 500-1200 J/kg range. Modestly increasing westerly mid/upper flow will support 20-30 kt effective shear magnitudes and somewhat elongated hodographs. A couple of strong storms capable of sub-severe wind gusts and hail will be possible as convection develops east/southeast into the eastern CO and western KS vicinity through the evening. Overall, severe potential appears limited at this time given the modest thermodynamic and kinematic environment. ...Leitman.. 08/26/2025 $$ = = = 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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .