Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0640 AM CST Wed Nov 19 2025 Valid 191300Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN PLAINS INTO THE OZARKS... ...SUMMARY... Isolated severe thunderstorms appear possible across the southern Plains into parts of the Ozarks, mainly late this afternoon into tonight. Large hail should be the main threat, but occasional gusty winds and perhaps a tornado or two may also occur. ...Southern Plains into the Ozarks... A mid/upper-level trough will move slowly eastward across the lower CO River Valley and Southwest today into tonight. Enhanced southwesterly mid-level flow will persist across much of the southern Plains into the Ozarks and vicinity through the period. A moist low-level airmass in place across south/central TX this morning will advance slowly northward across north TX and OK/AR in tandem with a surface warm front. Weak lee cyclogenesis should occur this evening and overnight across west TX as large-scale ascent preceding the slow-moving upper trough eventually overspreads the southern Plains. Nebulous forcing for much of the day casts significant uncertainty on convective development across the warm sector until later this evening. Still, it appears likely that thunderstorms will gradually increase in coverage this evening into early Thursday morning across the southern Plains with the approach of the upper trough. Modest low-level warm advection in the vicinity of the warm front and a developing dryline across west TX may also aid in convective development this evening. Most guidance continues to show moderate instability in place along/near these boundaries, with modestly steepened mid-level lapse rates present. This favorable thermodynamic environment, coupled with moderate to strong deep-layer shear given the enhanced southwesterly flow aloft, should promote organized updrafts. Current expectations are for a mix of supercells and multicells to develop and pose an isolated threat for mainly large hail. Where convection can remain surface-based this evening, some threat for occasional gusty winds and perhaps a tornado or two should also exist. With time, updraft interactions/mergers should result in a messy convective mode, especially with elevated thunderstorms to the north of the warm front. Still, at least some risk for severe hail may persist for much of the overnight/early Thursday morning period with this activity as it spreads east-northeastward across the southern Plains and parts of the Ozarks. ...Southeast Arizona/Southwest New Mexico... Cool mid-level temperatures will be in place over the Southwest as the upper trough progresses slowly eastward. Weak instability may develop across parts of southeast AZ/southwest NM and vicinity with filtered daytime heating. While small hail could occur with the stronger cores that develop this afternoon across this region, modest low-level moisture and buoyancy should limit the overall severe threat. ..Gleason/Broyles.. 11/19/2025Read more