Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
894 ACUS02 KWNS 290543 SWODY2 SPC AC 290542 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Wed Jul 29 2026 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER A SMALL PART OF SOUTH-CENTRAL SOUTH DAKOTA INTO CENTRAL NEBRASKA... ...SUMMARY... Widely scattered severe storms capable of mainly damaging wind gusts appear possible over south-central South Dakota into central Nebraska Thursday afternoon and evening. More sporadic occurrences of mainly damaging wind appear possible from the northern High Plains into the upper Mississippi Valley into the central Plains, the Raton Mesa vicinity, and the central and eastern Gulf Coast. ...Synopsis... A short-wave trough initially over the northern Plains Thursday morning will translate into the upper Midwest, while a trailing disturbance moves through the mid MO Valley. Some enhancement of the mid-level flow is forecast with the secondary system over the central Plains. In the low levels, a surface low is expected to track from SD into MN, along a cool front moving through the upper MS Valley and the northern Plains into the central Plains. A secondary low is forecast to deepen along the front over central KS. ...Northern High Plains into the upper Mississippi Valley and the central Plains... Latest model guidance continues to indicate showers and thunderstorms ongoing at 12Z Thursday across the northern Plains into the mid MO Valley, within a zone of forcing for ascent preceding the lead short-wave trough. A subset of that convection may linger into afternoon with associated cloud cover limiting daytime heating and resultant destabilization. Where stronger heating can occur, the presence of boundary-layer dewpoints in the 60s to low/mid 70s will contribute to MLCAPE up to 2000-3000 J/kg. Thunderstorms are expected to increase in coverage and intensity during the afternoon in the vicinity of the cool front and any differential heating/outflow boundaries associated with previous and/or active convection. A separate area of storms may also develop later in the afternoon over eastern MT in the vicinity of a surface low and lee trough. Damaging winds appear to be the primary hazard, though isolated occurrences of large hail are also possible. A number of physics-based models and AI guidance indicate a corridor from south-central SD into central or eastern NE as being a preferred location for upscale growth of storms into a cold-pool-driven MCS Thursday afternoon into evening, which would enhance the damaging-wind potential. That scenario appears plausible as the consensus of model guidance depicts that zone as having the most favorable overlap of moderate to strong instability and modest vertical shear. Given these considerations, a 15% wind probability contour and related level 2/Slight Risk have been included to account for that potential. Enhanced moisture transport and storm-relative inflow along a nocturnal low-level jet are likely to sustain a complex of storms with some damaging wind risk Thursday night, mainly over eastern KS into the mid MO Valley. ...Raton Mesa vicinity... Convergence along the southward-moving front and/or upslope in its immediate wake are expected to foster isolated to widely scattered storms by mid afternoon along the high terrain. While vertical will remain relatively weak, the presence of a steep-lapse-rate environment, featuring a deep, well-mixed boundary layer will support the potential for isolated severe wind gusts. ...Central and eastern Gulf Coast... Early-day thunderstorms are expected across portions of the far northeast Gulf and central FL Peninsula. To the north of that convection, model guidance indicates a corridor of moderate to strong instability developing by afternoon in the vicinity of a stalled front. Diurnally enhanced thunderstorms are expected within that zone of stronger air mass destabilization with steepening low-level lapse rates and high precipitable water content supportive of locally damaging wet microbursts. ..Mead.. 07/29/2026 $$