727 ACUS03 KWNS 191928 SWODY3 SPC AC 191927 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 PM CDT Fri Sep 19 2025 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong thunderstorms are possible across parts of the Great Plains and the Ohio Valley on Sunday, though organized severe thunderstorm potential remains uncertain. ...Discussion... A compact midlevel trough will advance eastward across the Upper Midwest on Sunday, while a broader large-scale trough encompasses much of the central CONUS. Several embedded shortwave impulses (some convectively induced/enhanced) will track eastward within the zonal midlevel flow across parts of the Ohio Valley, central Plains and northern Plains through the period. Given the low-amplitude nature of these impulses (and large differences in timing/evolution among model guidance), organized severe thunderstorm potential remains uncertain at this time. Nevertheless, a moist/moderately unstable air mass will be in place from the southern/central Plains eastward into parts of the OH Valley, and given the subtle areas of large-scale lift and locally enhanced midlevel flow, a broad area of strong-thunderstorm potential is evident. As the details regarding timing/evolution of the embedded shortwave troughs and related destabilization become clearer, one or more Marginal Risk areas may be warranted over the central/southern Plains and the Ohio Valley. ..Weinman.. 09/19/2025 $$