Major SoCal storm triggers evacuation orders in LA County amid flood threats

Axios

03-03-2025

A powerful atmospheric river -linked storm that began slamming Southern California on Wednesday prompted evacuation orders in Los Angeles County amid flood threats to burn scars from wildfires that erupted in January.
Threat level: Flood and flash flood watches and high-wind advisories have been issued across Southern California.
Zoom in: With the worst of the "significant storm system" set to hit Thursday with heavy rains and gusty winds, Santa Barbara County said on X an evacuation order was also issued for properties associated with a burn scar from the 2024 Lake Fire due to the potential for "flash flooding, debris flow."
In LA County, evacuation warnings were also set to take effect from 7am Thursday through 2pm Friday "due to high mudslide and debris flow risk," according to a statement posted on the LA Fire Department's website.
Among the recently burned areas that the LAFD notes are "especially susceptible to heavy rain" are those affected by the destructive Palisades Fire, including around the Getty Villa art museum, the Sunset Fire in the Hollywood Hills and the Hurst Fire in the San Fernando Valley.
Situation report: Ahead of the storm, California Gov. Gavin Newsom directed teams to take emergency measures to prevent debris flows from burn scar areas, with up to 2 inches of rainfall expected in some places.
The Cal OES Watershed and Debris Flow Task Force has "installed emergency protection materials," including straw wattles, compost silt socks, and silt fences "to contain hazardous materials from the Eaton and Palisades Fires from entering LA's creeks, rivers, and other bodies of water," per a Monday statement from the governor's office.
The task force "is coordinating locally requested materials such as K-rails to divert debris flow and has completed debris basin clean-up activities over the last month to mitigate potential impacts in vulnerable areas," the statement added.
Santa Monica-Malibu Unified School District said all Malibu schools would be closed Thursday and possibly Friday "due to road closures and weather concerns."
What to expect: While only light precipitation was expected on Wednesday evening, periods of moderate to heavy rain were forecast Thursday followed by scattered showers into Friday morning, per a National Weather Service LA forecast discussion.
UCLA climate scientist Daniel Swain noted in a Wednesday blog post that while the "whole region should see a good soaking, the SoCal mountains will see widespread 3-6 inch totals (locally higher), and that does include most of the major recent fire footprints."
Thunderstorms were expected to hit Southern California from noon to 10pm Thursday and rainfall rates of just over 1" per hour were expected across parts of Santa Barbara County and Ventura Counties, according to the NWS LA.
"However, any location is susceptible to rain rates between a half and one
inch per hour, especially during the peak of the event when convection is most likely," it added.
Meanwhile, heavy snow in addition to the rains was forecast in the Sierra Nevada.
Between the lines: Southern California had already been hit by " hydroclimate whiplash" from very wet to drought conditions ahead of the atmospheric river.
Swain said while it has "finally rained" in Southern California this winter, "nearly the entire region remains woefully behind average."
Human-caused climate change is leading to more frequent and intense extreme precipitation events, research shows.
Go deeper: Climate change made LA fires far more likely, study says
Editor's note: This article has been updated with new details throughout.