A powerful and unusually intense storm system, known as an atmospheric river, deluged Southern California on Saturday, November 15, 2025, leading to significant flood warnings and raising concerns about debris flows in areas recently scarred by wildfires.
Heavy Rainfall and Immediate Impacts
The National Weather Service offices in Los Angeles and Oxnard reported heavy rainfall on Saturday, with precipitation rates reaching up to an inch (2.5 centimeters) per hour in coastal regions particularly susceptible to flash flooding. This followed a day of substantial rainfall on Friday, where more than four inches of rain fell over coastal Santa Barbara County as the storm advanced.
The long plume of tropical moisture, which formed over the Pacific Ocean, began its onslaught in the San Francisco Bay Area on Wednesday before moving south. Authorities had strongly urged people to stay indoors due to the combination of heavy rain and strong winds.
Evacuations and Burn Scar Dangers
The storm's most severe threats were focused on recent burn scar areas, where the loss of vegetation dramatically increases the risk of mudslides and debris flows. Los Angeles Mayor Karen Bass confirmed in a social media post that an Evacuation Warning remained in effect for these vulnerable zones.
Mandatory evacuation orders were issued for specific high-risk properties within the Palisades and Eaton fire burn areas, effective from Friday evening through Sunday morning. Law enforcement personnel were proactively visiting properties in these zones to encourage residents to leave for their own safety.
Ongoing Warnings and Regional Effects
While the National Weather Service allowed some flood advisories and warnings within the City of Los Angeles to expire, a Flood Watch remained in effect for Los Angeles County through 8 p.m. on Saturday. Officials from UnifiedLA warned that localized flooding was still a significant possibility across the city.
The impacts of the storm were not confined to rain. More than a foot of snow was predicted for parts of the Sierra Nevada, and flood warnings had extended from the Ventura County coast, through Malibu, and into the City of Los Angeles, illustrating the widespread nature of this atmospheric river event.
