A major atmospheric river swept across Southern California from late December 24, 2025, into Christmas Day, December 25, triggering widespread flash floods, evacuations, debris flows, and power outages. Multiple counties including Los Angeles and Ventura were put under a State of Emergency. Rainfall totals reached 75–150 mm (3–6 inches) in coastal and valley areas, with up to 250 mm (10 inches) in higher terrain of Los Angeles and Ventura counties, prompting officials to urge residents to avoid travel.