Winter storm moves into Southern California, triggering flash-flood warnings and a mudslide that shut down PCH

LOS ANGELES – The first major storm of the new year moved into Southern California on Saturday night, triggering a mudslide that shut down a section of Pacific Coast highway and prompted flash flooding and debris flows near burn areas in Los Angeles and Ventura counties.

An automated rain gauge in the western Santa Monica Mountains showed nearly three-quarters of an inch of rainfall in one hour, the National Weather Service said.

PCH was closed in both directions from Encinal Canyon Road to west of the Los Angeles County line due to flooding, the city of Malibu tweeted. Three vehicles became stuck in the mud around 7 p.m. where Deer Creek Road intersects the highway.

The mud and debris were about 100 yards wide and up to 4 feet deep, Ventura County Fire Capt. Dennis O’Shea said.

“Some drivers actually stopped by our fire station and rang our doorbell to tell us there was flooding and people were trapped,” he said. “Those folks just happened to be in the worst part of it, and they just got stuck.”

The highway could be closed for at least 24 hours.

“We had 20 minutes of really hard rain, and the next thing you know we got the call,” O’Shea said. “The mud is very silty. It’s quicksand-type mud. It’s super heavy and dangerous.”

A flash-flood watch was issued for the burn areas of the Woolsey and Hill fires and will be in effect through midnight. The fires burned more than 100,000 acres in November, destroyed about 1,600 structures and claimed three lives.

A half-inch to 11/2 inches of rainfall is expected along the coasts and valleys, with higher amounts possible along south-facing foothills and mountains, said Kristen Stewart, a meteorologist with the National Weather Service in Oxnard.

Orange and San Diego counties are expected to see a quarter of an inch to 1 inch of precipitation in some cities over the weekend. The heaviest rain was expected to fall overnight, Stewart said. About twice as much in some inland valleys and hills in San Diego County.

Snowfall in the mountain regions of Los Angeles County could reach as low as 4,500 feet, Stewart said. High surf is also predicted from 5 to 8 feet, she said.

Malibu officials are advising residents to prepare for potential flooding, mudslides, power outages, dangerous road conditions and possible evacuations.

City officials have released a map of burn areas that show where the potential for flooding and mudslides is greatest. The city is also providing free, empty sandbags at Malibu-area fire stations and pre-filled sandbags at the Zuma Beach lifeguard headquarters.

In Ventura County, the city of Oxnard opened a shelter Saturday evening, city officials said. The shelter, at the Armory at 351 North K St., opened at 4 p.m.; if the weather improves, the site will close at 9 a.m. Sunday.

Meanwhile, burn areas in the northern region of the state appeared to escape heavy rainfall as the chilly Pacific storm passed through the area earlier Saturday.

The Bay Area and Northern California saw mostly light rain, including about a half-inch in and around Paradise in Butte County where the state’s deadliest and most destructive fire burned in November, said Steve Anderson, a meteorologist with the National Weather Service. The Camp fire charred more than 153,000 acres, destroyed nearly 14,000 homes and killed at least 84 people.

But the region seemed to sidestep another possible disaster on Saturday.

“There are no reports of flooding. It is pretty light rain,” Anderson said.

The heaviest rain in the region – about 21/4 inches – fell around the Big Sur coast.

A moderate El Nino weather pattern that is brewing in the eastern tropical Pacific Ocean is bringing more precipitation to some regions of California. The weather outlook for the next several weeks indicates above-normal precipitation; in the next few months, the odds are looking good for above-average rainfall, weather experts said.