SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0741 PM CDT Sat Oct 11 2025 Valid 120100Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE EASTER GREAT BASIN AND SOUTHWEST...AND ALONG THE NORTH CAROLINA OUTER BANKS REGION... ...SUMMARY... Isolated severe thunderstorms remain possible this evening across the eastern Great Basin and Southwest. A brief tornado and occasional strong to severe gusts could occur over the Outer Banks of North Carolina late tonight and early Sunday morning. ...01z Update... Strong progressive upper trough is advancing steadily across the northern Intermountain region and Great Basin early this evening. Strong midlevel height falls and high-level diffluent flow continue to favor scattered convection along the frontal zone as it shifts east this evening. 00z sounding from SLC exhibited relatively steep lapse rates through 5km with MLCAPE around 700 J/kg. Nocturnal cooling should weaken boundary-layer lapse rates over the next few hours which should lead to overall weakening of ongoing activity. Farther south across southeast AZ, fairly high PW values are noted along the U.S. side of the international border with 1.66 PW observed at TUS. Deep-layer flow is also modestly strong which will continue to support at least isolated severe within an air mass characterized by MLCAPE around 1100 J/kg. This activity should spread toward southwest NM where cooler temperatures and weaker buoyancy will lead to weaker updrafts. Boundary layer moisture is gradually increasing along the Outer Banks of NC early this evening where latest observational data suggests lower 70s are noted. As moisture/instability advance inland the prospect for deeper updrafts/lightning will increase, especially after midnight. Some risk for severe gusts and perhaps a brief tornado can be expected. ..Darrow.. 10/12/2025
