SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Thu Oct 02 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES INTO THE FOUR CORNERS... ...SUMMARY... Isolated severe gusts and perhaps a couple instances of hail may occur across the northern Rockies into the Four Corners tomorrow (Friday). ...Synopsis... A pronounced mid-level trough will progress across the Interior West while upper ridging persists east of the Rockies tomorrow (Friday). The approach of the upper trough will encourage surface low development over the northern Plains, with appreciable low-level moisture return expected across the Plains and MS Valley. Given limited forcing for ascent east of the Rockies, thunderstorm development should be limited to the warm front over the Upper MS Valley, and along the Gulf Coast with low-level moisture pivoting around a surface high along the East Coast. West of the Rockies though, where upper support is present, cooler temperatures aloft will promote enough buoyancy to support scattered thunderstorm development. Given stronger flow aloft and associated vertical wind shear, some storms could become strong and sustained. ...Portions of the Northern Rockies to the Four Corners... Scattered thunderstorms will develop by afternoon ahead of the upper trough, once a well-mixed boundary layer, extending over 600 mb, becomes established. Temperatures will warm into the 70s F, beneath 7-8 C/km lapse rates, resulting in a few hundred J/kg MLCAPE. This buoyancy will be constrained to thin profiles, which may limit the severe threat to some degree. Nonetheless, a 50-70 kt 500 mb jet streak will impinge on the Northern Rockies to Four Corners regions, resulting in elongated and modestly curved hodographs. High-based, fast-moving multicells are the expected mode of convection, with strong wind gusts likely. A few severe gusts may occur, along with an instance or two of hail, warranting Category 1/Marginal risk probabilities across the northern Rockies to the Four Corners. ..Squitieri.. 10/02/2025
