Overview: An Atmospheric River Tests Southern California
An atmospheric river slammed into Southern California in the early hours of Tuesday, bringing a burst of heavy rain, gusty winds, and widespread concerns about flooding and debris flows. The storm’s reach extended from the burn scars of January’s wildfires in the Palisades and nearby areas to the Central Coast, where rare tornado warnings were issued. Meteorologists warn that burn scars and steep canyons will be particularly vulnerable, with the potential for dangerous debris flows as soils struggle to absorb rain.
Immediate Impacts Across Los Angeles County
As of 8 a.m., the storm was projected to strike the Palisades fire burn scar, with rainfall rates expected to reach 1 to 1.5 inches per hour. The National Weather Service issued a flash flood warning for the affected area, including the Franklin fire burn scar in Malibu. Burned soils repel water, meaning faster runoffs and a heightened risk of flash floods and debris flows. A separate severe thunderstorm warning covered parts of west central Los Angeles County, with the possibility of 60 mph gusts and hail that could damage roofs and trees.
A flash flood watch remained in effect for most of the county through Tuesday afternoon, with the heaviest rainfall anticipated between 9 and 11 a.m. Weather officials described the system as rare and potent, capable of producing mudslides, thunder, hail, and gusty winds that could topple trees or power lines.
What About Road Conditions and Getting Around?
Early Tuesday morning, road flooding was reported across several corridors, including Hueneme Road near Olds Road in Mar Vista, the 101 near Seward Avenue in Ventura, and I-5 near Sheldon Road in Sun Valley. In some places, rock and mud blocked roads, and a downed tree forced lanes to close in Encino. Authorities urged drivers to avoid flooded roadways and seek shelter indoors if rain intensifies.
Santa Barbara and Ventura Counties: Tornado Warnings and Heavy Downpours
Before arriving in Southern California, the storm dumped heavy precipitation in Northern and Central California. In San Luis Obispo County, the system triggered rare tornado warnings for areas such as Pismo Beach, Nipomo, and Oceano, with rainfall rates up to 2.5 inches per hour at times. In Ventura County’s mountains, higher elevations saw rainfall rates as high as 3.5 inches per hour, accompanied by reports of downed trees, rocks, and debris.
Forecasts and Warnings: What the Weather Service Expects
In Los Angeles County, total rainfall is forecast to range from 0.75 to 1.5 inches in coastal and valley zones, and 2 to 4 inches in foothill and mountain areas. The system will push temperatures several degrees below normal, and a multi-county flash flood warning remained in effect for much of Ventura County, parts of northern Santa Barbara County, and inland Orange County. Officials warned that peak rainfall rates will likely occur Tuesday morning, with canyon road rockslides considered nearly certain.
Preparation and Public Safety
City and county authorities distributed sandbags to protect vulnerable areas, and law enforcement conducted door-to-door notices in burn scar zones about debris-flow risks. Emergency services prepared with specialized response teams, including strike teams, hand crews, urban search-and-rescue, and swift-water units, ready to respond to flooding and mudslides. Residents were urged to sign up for emergency alerts at NotifyLA.org and to heed evacuation warnings, recognizing that conditions can change quickly and that debris flows can trap responders if not anticipated in time.
Looking Ahead: Clearance and Warmer Days Return
The storm’s lingering showers are expected to taper by late Wednesday, followed by drying and warming winds. By Thursday, Southern California’s climate should return to more typical October conditions, with pleasant temperatures in the 70s across Los Angeles County.
