Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
836 ACUS02 KWNS 301658 SWODY2 SPC AC 301656 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1156 AM CDT Wed Sep 30 2026 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF KANSAS...OKLAHOMA...AND TEXAS... ...SUMMARY... Isolated severe storms capable of mainly severe wind gusts appear possible over portions of Kansas, Oklahoma, and Texas Thursday afternoon and evening. ...Synopsis... An upper low initially over the central and southern High Plains Thursday morning is forecast to break down into a positively tilted, open wave with a series of vorticity maxima spreading from KS and OK into the Great Lakes and OH Valley. At the surface, a cold front stretching from the Great Lakes into the central High Plains at the start of the period will advance south into the OH and mid MS Valleys, Ozark Plateau, and the southern Plains by Thursday night. That boundary will progressively overtake a north-south-oriented Pacific front, which will become quasi-stationary over the southern Plains. ...Kansas, Oklahoma, and Texas... A band of showers and thunderstorms is likely to be ongoing at 12Z Thursday from eastern KS and western MO into central TX within the warm-conveyor air stream preceding the weakening mid-level system. A subset of those storms is likely to continue through the day, fueled by a very moist and at least marginally unstable air mass and within the right entrance region of an upper-level jet streak progressing northeast away from the region. In areas peripheral to active convection where stronger heating can occur, pockets of moderate instability are expected to develop by mid to late afternoon. Based on 12Z guidance, a couple areas appear more favorable for at least isolated severe storm development during the afternoon into evening. The first is over southern KS and northern OK where an overlap of stronger deep-layer shear and moderate buoyancy is expected to materialized ahead of the cold front. Multicell and transient supercell storm modes appear possible with an associated risk for locally severe wind gusts and/or marginally severe hail. AI-based guidance hints at some tornado threat; however, the southward-advancing cold front may tend to undercut surface-based storms forming along it, effectively limiting the potential. The other area is over Deep South TX where afternoon storms will have access to a reservoir of greater instability (MLCAPE up to 2500 J/kg). While vertical shear is expected to remain weak, the presence of a very moist air mass will support the potential for locally intense wet microbursts capable of severe wind gusts. ..Mead.. 09/30/2026 $$