SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0755 PM CDT Thu Jun 26 2025 Valid 270100Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE NEXT COUPLE OF HOURS ACROSS EASTERN IOWA INTO SOUTHWESTERN WISCONSIN... ...SUMMARY... Isolated wind damage and marginally severe hail will be the main threats through late evening/early tonight from eastern Kansas into southern Wisconsin, parts of the Mid-Atlantic and Appalachians, the Texas Panhandle, and eastern Montana. ...Eastern KS to southern WI through late evening... Convection has evolved into a line of storms from northwest MO into eastern IA and southwest WI along a conglomerate outflow, in advance of a weak midlevel trough approaching the upper MS Valley. Weakening buoyancy with the loss of daytime heating and weakening vertical shear over time in the warm sector suggests that the storms are likely past peak, though isolated wind damage will remain possible for the next 2 hours or so before the storms weaken sufficiently and the low levels stabilize. ...Mid-Atlantic and Appalachians through 03z... Scattered thunderstorms are ongoing in multiple small clusters from central NC into VA/WV/MD and southern PA. A few strong storms with isolated wind damage will be possible through about 02-03z, especially with storm mergers, before gradual stabilization of the boundary layer brings an end to the largely diurnal severe threat. ...TX Panhandle through late evening... A few storm clusters are ongoing across the central TX Panhandle to the TX/NM state line. Lingering steep low-level lapse rates, modest vertical shear and storm/outflow mergers could maintain a marginal severe threat for another few hours before buoyancy weakens and the storms diminish. ...Eastern MT this evening... Deep-layer vertical shear is not particularly strong and low-level moisture is limited, but steep lapse rates through the low-midlevels are sustaining a couple of stronger storm clusters across northeast MT where low-level moisture is a bit richer. There will remain sufficient midlevel moisture/ascent downstream of an ejecting midlevel trough to maintain the potential for thunderstorms for the next several hours. Isolated strong outflow gusts may occur with the high-based convection into central MT, while isolated strong gusts and marginally severe hail will remain possible this evening across eastern MT. ..Thompson.. 06/27/2025