Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
405 ACUS48 KWNS 290841 SWOD48 SPC AC 290839 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0339 AM CDT Wed Jul 29 2026 Valid 011200Z - 061200Z ...DISCUSSION... ...Day 4/Saturday... A short-wave trough will progress from the mid MS into lower OH Valleys with modest height falls forecast across the Gulf Coast states. At the surface, an area of low pressure will follow the same track as the upper-air system, while a trailing cold front advances through the lower MS and TN Valleys. While weaker than on Friday, a modest enhancement of 850-mb winds is forecast during the afternoon ahead of the surface low over the OH and TN Valleys. Morning storms appear possible from the lower OH into lower MS Valleys within a zone of warm advection associated with a nocturnal low-level jet. The longevity and extent of early-day storms remain uncertain, but where stronger heating can occur, the presence of boundary-layer dewpoints in the 70s will contribute to pockets of moderate instability. Additional storms are anticipated during the afternoon, focused along the cold front and any residual outflow boundaries from previous storms. Deep-layer shear is expected to remain generally less than 30 kt, which will tend to limit the potential for organized storm modes. A possible exception is across parts of KY and TN where slightly stronger low-level shear could contribute to updraft rotation and some tornado risk. Otherwise, locally damaging wind gusts appear to be the primary hazard. Isolated severe storms capable of mainly damaging winds and hail appear possible over the southern High Plains Saturday afternoon and evening within a moist and unstable upslope regime. ...Days 5 and 6/Sunday and Monday... The models remain in relatively good agreement in depicting a strong short-wave trough and attending belt of mid-level flow progressing along the international border from the northern Rockies into the northern Plains. Low-level ridging from the Great Lakes into southern Plains may disrupt the return of robust boundary-layer moisture ahead of a cold front moving through the northern Plains into the upper MS Valley. Nonetheless, the presence of steep lapse rates and strengthening vertical shear along the frontal zone will support some severe weather risk over the northern Plains on Sunday and the northern Plains into the upper MS Valley on Monday. An isolated severe storm threat may also develop along the East Coast on Sunday, ahead of a positively tilted trough moving through the Great Lakes and OH and TN Valley. ...Days 7 and 8/Tuesday and Wednesday... The 00Z ensemble means indicate a belt of modestly enhanced mid-level flow from the northern Rockies into the Great Lakes, between a trough over Hudson Bay and a flattened ridge across the Southwest. Some severe weather threat may materialize over the central High Plains along and to the north of a stalled front, and perhaps in AZ if stronger easterly flow can develop on the south side of the upper high. ..Mead.. 07/29/2026