SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0151 PM CST Wed Nov 12 2025 Valid 122000Z - 131200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms remain possible along the coast of northern California late tonight/early tomorrow. No severe threat is forecast across the U.S. today or tonight. ...20z Update... No changes were made to the current outlook. Isolated thunderstorms remain possible late tonight ahead of an upper trough moving onshore over northern CA near 12z. Severe potential is low, see the prior outlook for more info. ..Lyons.. 11/12/2025 .PREV DISCUSSION... /ISSUED 1027 AM CST Wed Nov 12 2025/ ...Synopsis... An amplified upper pattern will persist across the CONUS today/tonight, characterized by a trough across the eastern states and an upper ridge over the West. At the surface, a mostly dry/stable airmass will be in place, precluding thunderstorm activity for most of the forecast period. Late tonight, an upper low will progress eastward eastern Pacific, approaching the offshore waters near northern CA. As height falls overspread the Pacific coast, a surface low will deepen offshore. A line of elevated convection is expected to develop ahead of a cold front and move onshore in the 08-12z time frame. Cooling aloft will support weak elevated instability, and isolated thunderstorms will be possible. Severe storms are not expected.
