SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0732 AM CDT Fri Oct 10 2025 Valid 101300Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...Synopsis and Discussion... Rich low-level moisture present over southern AZ and the Lower CO River Valley this morning will spread northward today as an upper trough/low moves slowly inland along the West Coast. Across the Great Basin, lapse rates aloft are forecast to remain fairly modest, and daytime heating will likely be hindered to some extent by mid/high-level cloudiness. Still, at least weak instability should develop by late afternoon, which combined with increasing mid-level flow with the approach of the upper trough/low may support a strong thunderstorm or two. However, the overall severe threat appears too isolated/marginal to include any hail/wind probabilities across the southern Great Basin and vicinity with this update. Elsewhere, ongoing elevated thunderstorms aided by a westerly low-level jet may persist through the morning over MO and IL before eventually weakening. Isolated to scattered thunderstorms may also occur today across parts of the FL Peninsula/Keys, Great Lakes, and Pacific Northwest/northern Rockies. Across all these regions, the forecast combination of instability and shear appears inadequate for organized severe convection. ..Gleason/Squitieri.. 10/10/2025
