Overview
- The National Weather Service expects the system between Dec. 23–26, with Northern California and the Sierra possibly seeing heavy precipitation starting as early as Dec. 21.
- Coastal and valley areas in Southern California are projected to receive 2–4 inches of rain, with foothills and mountains potentially up to twice that.
- County guidance shows high rain probabilities on Dec. 24–25 across Los Angeles, Ventura, Santa Barbara, Orange, Riverside and San Bernardino counties, reaching 80–100% in many locations.
- Forecasters cite risks that include slick roads, possible chain requirements or closures on major passes such as the Grapevine, flash flooding and landslides in burn areas.
- Officials advise carrying snow chains and a winter kit for mountain travel, keeping fuel tanks topped off, clearing gutters at home, and securing outdoor decorations ahead of gusty winds.