SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CST Thu Jan 01 2026 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHEAST AND NORTHERN CA TO COASTAL SOUTHWEST OR... ...SUMMARY... Isolated severe storms are possible across parts of the Southeast on Saturday, and the Sacramento Valley to coastal northern California-southwest Oregon during the late afternoon to evening. ...Southeast... A lower-amplitude shortwave trough should progress east across the Lower MS Valley on Saturday morning and off the South Atlantic Coast by Saturday night. Attendant surface cyclone should remain weak and track from central AL to off coastal SC by evening. Timing of large-scale ascent with the trough should yield increasing convective coverage by late morning to midday, focused along the northeast Gulf Coast to the Savannah Valley. Much of the region should remain within the MLCAPE gradient as a plume of moderate buoyancy becomes established over the northwest Gulf to central Gulf Coast. Guidance consensus suggests that low-level winds may gradually dampen through the day and become displaced east of richer boundary-layer moisture as the surface low moves towards the coast. With a predominately west-southwesterly wind profile, deep-layer speed shear should be the primary driver of organized convection. A mix of all hazards appears plausible, although a corridor of greater damaging wind potential may be evident in later outlooks. ...Northern CA to coastal southwest OR... Guidance appears to be converging towards multiple shortwave impulses ejecting northeast from a large-scale trough off the West Coast. The more vigorous impulse should impinge on coastal OR around Saturday evening, while a separate impulse dampens from the Bay Area to the Sierra NV Mountains on Saturday afternoon. The southern impulse should be favorably timed with afternoon boundary-layer heating over the Sacramento Valley, where meager MLCAPE of 250-500 J/kg may develop. Amid a swath of strong mid-level south-southwesterlies, an elongated hodograph could favor splitting weak supercell structures that pose a risk for a brief tornado and small hail. The northern impulse should be accompanied by very strong low-level southerlies from 60-70 kts at 850 mb. While buoyancy will remain scant, low-topped convection along the northern CA to southwest OR coast could pose a threat for severe gusts. ..Grams.. 01/01/2026
