More heavy rain swamps Southern California; flood warnings, watches around Los Angeles

Heavy rainfall battered Los Angeles on Monday as four counties in Southern California were placed under a flood watch just two weeks after a fierce winter storm devastated the region with severe flooding and mudslides.

The National Weather Service placed wide swaths of Los Angeles County's inland coast under a flood watch through Wednesday. On Monday, the western side of the city Los Angeles and the Santa Monica Mountains were under a flash flood warning until 6 p.m.

Flood warnings were also issued for the San Fernando and San Gabriel Valleys and the Eastern Santa Monica mountains.

"The main flood threat is going to be today and tomorrow," AccuWeather Meteorologist Joseph Bauer told USA TODAY on Monday.

The storm could bring up to 5 inches of rain and "damaging" winds of up to 60 mph, the weather service said. Mountainous areas could see several feet of snow and up to 8 inches of rain.

The rainstorm descended on the Central Valley late Sunday and stretched south to soak San Diego, according to AccuWeather. Bauer said Monday's rain would cover the region northwest of the L.A. basin, and the heaviest rainfall will hit Santa Barbara and Ventura County.

"They've already picked up a couple inches around Santa Barbara and even produced some flash flood reports in Santa Barbara itself and into the hills," Bauer said.

The California Governor’s Office of Emergency Services activated its operations center over the weekend and positioned personnel and equipment in areas most at risk.

Feb 6, 2024; Studio City, Calif., USA; Homeowners evacuate their homes in Studio City where a large mud slide destroyed multiple homes in the area. A powerful atmospheric river storm deluged California on Monday with more heavy rain, mudslides, flooding and several feet of snow in the mountains. The brunt of Monday's storms centered on the Los Angeles area, where 1.4 million people were under a flash flood warning – including the Hollywood Hills and Beverly Hills. Additional rainfall totals of 5-8 inches were forecast in some areas, which would bring 48-hour totals as high as 14 inches for some locations, the weather service said. A state of emergency was declared in eight Southern California counties. Mandatory Credit: Yannick Peterhans-USA TODAY ORG XMIT: USAT-749889 ORIG FILE ID: 20240206_aa9_usa_004.JPG

Several rescues done, flooding closes Santa Barbara airport

The storm led to a number of rescues from northern to central California.

In Sloughhouse, a community about 20 miles southeast of Sacramento, firefighters rescued two people from the top of their vehicle that had stalled in flood waters, the Sacramento Metropolitan Fire District said.

And hours earlier, a man was rescued along a creek in El Dorado Hills, just northeast of Sacramento. The man, who had been camping in the area, was trapped in a tree as floodwaters rose, El Dorado Hills Deputy Fire Chief Dave Brady told KCRA-TV.

In San Luis Obispo County, on the state's central coast, crews helped three people out of the rising Salinas River in the city of Paso Robles. Firefighters were already planning to train on swift-water rescues when they received word that someone was stranded on an island in the river, Paso Robles Fire and Emergency Services Battalion Chief Scott Hallett told KSBY-TV.

The Santa Barbara airport closed Monday after as much as 10 inches of rain had fallen in the area by noon, covering the runways with water. All commercial flights were canceled and airport officials paused general aviation operations.

"Santa Barbara Airport remains closed until further notice," airport officials said in a statement late Monday afternoon. "The airfield experienced significant flooding due to the storm and water is not expected to recede enough to open for the reminder of today."

Flooding, mudslides, power outages all possible

The storm would then move south down the coast on Tuesday, centering on the L.A. basin and bringing "concerns for flooding and mudslides" in the area, he said. Metro areas in Los Angeles and San Diego are at risk of "ponding water," Bauer said.

The weather service warned residents of all four counties in Southwest California to look out for rock and mudslides caused by the torrential rain.

Bauer said the heavy rainfall could also trigger power outages. "You've got a more elevated risk for downed power lines and trees falling into power infrastructure there because of the saturated ground," Bauer said.

High surf and coastal flooding are also expected through Tuesday on the beaches of Los Angeles and Malibu, and Santa Barbara County could see waves of up to 20 feet, the weather service said. The agency advised residents to avoid flooded roadways and dangerously large waves on the coast.

Northern California was not out of the woods. Bauer said San Francisco and the Central Inner Valley could also face some severe weather on Monday. "We're portraying some risk of severe weather today, which includes the risk for downpours and even some isolated tornadoes in that corridor as well," Bauer said.

Dramatic photos: Flooding makes fourth wettest day in San Diego

A 'level down' from severe storm in early February

The new bout of rain comes just two weeks after a severe storm, dubbed the "Pineapple Express," soaked California in the heaviest rain of the season and triggered widespread, dangerous flooding throughout the area. In response to the extreme weather, eight counties in Southern California declared a state of emergency.

Los Angeles recorded more than 4 inches of rain on Feb. 4, breaking the day's record by more than an inch and totaling the most rain in one day in more than 20 years. Some areas in Southern California saw up to 8 inches of rain.

The rainfall and mudslides created up to $11 billion worth in damage to infrastructure and economic loss, according to preliminary reports from AccuWeather.

Bauer said this week's rainfall would be a "level down" from the last storm.

"That was a historic event," he said. "This one is not going to quite produce that much rainfall."

Atmospheric rivers are fueling these storms

Atmospheric rivers are behind both this week's rainfall and early February's storm. The threads of water vapor, which spread from the tropics and stretch hundreds of miles across, cause around half of all annual precipitation on the West Coast.

"If you look at the satellite this morning, you can see a stream of moisture along the tail end of this cold front here that really stretches all the way from the area east of Hawaii, pulling up all that tropical moisture toward Southern California," Bauer said.

Contributing: The Associated Press

Cybele Mayes-Osterman is a breaking news reporter for USA Today. Reach her on email at cmayesosterman@usatoday.com. Follow her on X @CybeleMO.

This article originally appeared on USA TODAY: Southern California hit with another winter storm, heavy rainfall