Hilary Leaves Massive Flooding, Mudslides, Upheaval Across Southern California

LOS ANGELES — In the wake of Hilary’s lashing of Southern California, the region awoke Monday to lingering damage from the historic storm, with parts of San Bernardino reporting mud and debris slides that closed roads and stranded firefighters.

At San Bernardino County Fire Station 99 in Forest Falls, a small, unincorporated community near the El Dorado burn scar, the lashing rains from the remnants of Hurricane Hilary transformed a wooded, rocky area near the station into a roaring mudslide, forcing firefighters to run for safety.

According to a video from OnScene, the firefighters at Station 99 said they were inside the station when they heard rumbling noises. They hiked up a small hill behind the station, where they recorded video of brown waters that quickly swelled into a wave of rock, downed tree trunks, and other debris rushing down the hillside and onto the roadway. The firefighters reported that access to the station was completely blocked in both directions, according to OnScene.

Officials at the station could not be reached for comment early Monday morning.

A helicopter took flight at first light Monday morning to assess the damage across the area, focusing on such communities as Forest Falls, Oak Glen, and Seven Oaks, where locations had “numerous residents sheltered in place” because debris and mud flow rendered roads impassable, said Alison Hesterly, public information officer and battalion chief for Cal Fire San Bernardino.

County agencies dispatched teams early Monday to survey the damage and determine next steps, she said. Additional updates were not immediately available.

The first tropical storm to hit Southern California in 84 years dumped record rainfall and turned streets into muddy, debris-swollen rivers; downed trees and knocked out power for thousands of residents; and closed schools across the Southland.

During a morning update at the city’s Emergency Operations Center, Mayor Karen Bass said no deaths were reported in Los Angeles due to the storm.

Crews from L.A. city agencies were responding to downed power lines, toppled trees, damaged streets, and clogged storm drains, Bass said. About 18,000 customers of the Los Angeles Department of Water and Power were without power Monday morning, including residents of Hollywood, Pico-Union, and Beverly Grove, according to Marty Adams, the top executive of the city’s utility.

Hilary was downgraded to a post-tropical storm early Monday, the National Hurricane Center said in an advisory. But even in its weakened state, it was still predicted to bring “catastrophic and life-threatening flooding” to parts of the southwestern U.S., the center said.

The center of the storm was over Nevada early Monday. But forecasters warned Southern California residents to brace for more rainfall, including a slight chance of thunderstorms, as well as strong winds, with gusts of up to 50 mph possible at higher elevations.

Hilary broke “virtually all rainfall daily records” for Sunday, the National Weather Service in Oxnard said on X, formerly known as Twitter. Among the more impressive totals were in Lewis Ranch, which recorded 7.04 inches of rain; Lake Palmdale, which reported 5.98 inches; UCLA, with 4.26 inches; Thousand Oaks, with 3.29 inches; and downtown Los Angeles, with 2.38 inches.

Rose Schoenfeld, a meteorologist with the weather service in Oxnard, said the biggest impact from Hilary was flash flooding throughout the region, with significant flooding in the Antelope Valley and parts of L.A. County and Ventura County.

On Sunday, Highway 138 in the Antelope Valley was closed by running water and debris flows.

Flooding on 5 Freeway in Sun Valley severely limited access to northbound lanes early Monday. Only two lanes of the five-lane highway were open at Lankershim Boulevard due to flooding and mud debris, according to the California Department of Transportation.

Outside L.A., about 20,000 customers were without power in Southern California on Monday morning, according to Southern California Edison’s website. SCE President and Chief Executive Steve Powell told CNN that crews have been dispatched to restore electricity in affected areas.

Many areas across the coastal slopes and foothills in Los Angeles County and parts of Ventura County could receive up to 2 inches of additional rainfall Monday because of “very moist southwest flow” in the area, the weather service said.

Northern L.A. County and eastern Ventura County remained under a flood advisory until 8 a.m. Southern California’s mountains recorded some of the highest wind speeds Sunday into early Monday, with gusts reaching well over 40 mph, and as high as 80 mph in the western San Gabriel, San Bernardino, and San Diego County mountains, according to the National Weather Service.

In Riverside County, Palm Springs said in a post on Facebook that its 911 lines were down early Monday. Residents were advised to text 911.

The Coachella Valley saw 2 to 4 inches of rain at lower elevations, including in Palm Springs and Indio, and about 4 to 6 inches farther west, the National Weather Service said.

Luz Gallegos, executive director of the nonprofit immigrant assistance group TODEC, said the organization helped coordinate transportation Sunday with county officials for several families in Thermal and Mecca who needed shelter. Monday’s efforts are focused on “recovery,” with teams out to assist families in the Inland Empire and Coachella Valley, Gallegos said. The main concern is for farmworkers who are unable to work, and she said her group was preparing to bring supplies, including rain gear, to workers on a ranch on the west end of Riverside County.

A section of the 10 Freeway in Riverside County near Indio remained closed “until further notice,” officials said early Monday, and debris flows in San Bernardino County had affected multiple roadways.

In the San Bernardino County mountains, the communities of Wrightwood, Forrest Falls, and Oak Glenn were hit with heavy debris flows Sunday, and recovery efforts were expected to begin Monday morning.

Brian Adams, a meteorologist with the National Weather Service in San Diego, said flooding remains a concern in the area.

“Any little bit of additional rainfall is going to probably cause some hazards out there,” Adams said.

Hilary wasn’t the only threat to strike Southern California in the last 24 hours. A magnitude 5.1 earthquake struck near Ojai on Sunday afternoon, rattling the region. No damage was immediately reported.

Scientists were quick to say there was no connection between Hilary and the quake.

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(Times staff writer Brittny Mejia, David Zahniser, and Richard Winton contributed to this report.)

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