SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Fri Oct 10 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE EASTERN GREAT BASIN...THE CO PLATEAU...AND THE NC OUTER BANKS... ...SUMMARY... Isolated severe thunderstorms are possible on Saturday afternoon into the evening across the eastern Great Basin and the Colorado Plateau. A brief tornado and a severe gust are possible over the Outer Banks of North Carolina during the early morning Sunday. ...Eastern Great Basin and the CO Plateau... A broad upper trough will move east across the West as a basal shortwave impulse ejects across the Great Basin during Saturday afternoon and evening. This evolution will yield a swath of strengthening mid/upper-level southwesterlies. This will be favorably timed with peak surface heating across the eastern Great Basin into parts of the CO Plateau. In the wake of weak morning convection across parts of AZ across the Four Corners, scattered to widespread convection will occur in the afternoon along/ahead of the sharpening Pacific cold front as it pushes east. While MLCAPE will remain weak, owing to progressively poorer mid-level lapse rates with southeast extent and cooler surface temperatures/dew points to the northwest, strengthening deep-layer speed shear will yield elongation of a fairly straight-line hodograph. A few supercells are likely, although the weak mid-level lapse rates/buoyancy should support primarily a marginal severe hail threat. A tornado is possible in the Four Corners vicinity where boundary-layer moisture is greater. Given the degree of convective coverage, upscale growth into clusters/short-line segments should occur, fostering potential for sporadic severe gusts into early/mid-evening across the CO Plateau. ...NC Outer Banks... Morning NCEP guidance has trended closer to the coast with the evolution of a gradually deepening surface cyclone off the South Atlantic coast. This may result in the surface warm front advancing across the Outer Banks between 06-12Z Sunday, with a conditionally supportive environment for a surface-based supercell. While the bulk of surface-based convection should remain confined offshore through the period, there's enough signal to warrant a low-probability threat of a brief tornado/severe gust. ..Grams.. 10/10/2025
