Storm Unleashes Mud on Denuded Hillsides : Weather: Slides hit Malibu, but Laguna fares OK in intense downpour. Cyclonic winds rip through Irvine.

Intense downpours from the most powerful storm of the winter lashed the fire-denuded hillsides of Southern California on Monday, setting loose mudslides that surged through beachfront houses in Malibu and cyclonic winds that ripped through Irvine.

Winds gusted to 50 m.p.h. as the main force of the storm marched onshore, rocking outlying areas with thunder claps. A waterspout was reported off Santa Barbara, and the tornadolike winds cut a swath through part of Orange County, snapping trees, blowing out windows and snatching patches of roofs from buildings.

In Malibu, water, mud and rocks coursed down the canyons to the sea, invading homes and blocking portions of Pacific Coast Highway between Topanga Canyon Boulevard and Malibu Canyon Road.

A delta of debris washed out of Big Rock Canyon Road and across Pacific Coast Highway, sloshing against about a dozen houses and scattering half a dozen cars and trucks like sandbox toys.

Homeowners and emergency crews struggled through the muck, trying to plug makeshift dikes with sandbags. But despite their efforts, mud began seeping into shorefront homes and about 15 houses farther inland at Big Rock and in Las Flores Canyon.

More than 30 residents were forced to evacuate. A big Caltrans skip-loader was used to pluck several of them from their roofs, where they had taken refuge from the rising mud and water.

In Orange County, two people suffered cuts and bruises when struck by falling trees, said Kathleen Cha, spokeswoman for the County Fire Department.

Damage was reported as far south as MacArthur Boulevard in Newport Beach and as far north as Foothill Boulevard in Cowan Heights, but the most havoc hit Irvine, as the winds whipped north along Von Karman Avenue from Santa Ana Heights to the Tustin Marine Corps Air Station about 6:45 p.m. Power outages dotted Irvine and Tustin as trees large and small littered streets, blocked driveways and covered cars.

“All of a sudden we heard kind of a boom, and I looked outside the window and there was just a white sheet of water,” said Michele Herbel, a Rancho Santa Margarita resident who was working late at her office at Von Karman and Barranca when the winds hit. “It was dark outside but there was a flurry of white splashing water outside the window and you could not see. It seemed to last forever.”

Officials from the National Weather Service and WeatherData, Inc. could not say Monday night what caused the winds nor whether there had in fact been a tornado. Cha called it a “tornado-like event” but said she was unsure whether the winds had been 75 m.p.h., which is the threshold for a tornado.

“If it wasn’t a tornado it was pretty darn close,” said Marine Col. Bill Hammerle, who was watching television with his 4 1/2-year-old son when it went black as the winds whipped through the Tustin base.

At the base, roofs leaked and shingles fell from several residences, the roof of the fire department was partially blown off, and trees had crashed around the grounds, Hammerle said.

Vince Beres, who works at a Tustin gas station on Red Hill Avenue near the freeway, said the winds shattered his station’s windows, scattered debris, twisted a fence and moved an 80-pound sign across the street.

“The rain was coming down in sheets,” he said. “Then I saw the freeway sign, which is gone now, go flying by.”

The damage appeared most severe south of the marine base, in Irvine, where the winds sped along Von Karman Avenue through a light-industrial park, according to Irvine Sgt. Tom Hume.

Police closed Von Karman between Main Street and Barranca Parkway for much of the evening. Throughout the area, windows had been shattered, roofs ruined and trees thrown to the ground.

Throughout the day Monday, the storm caused snarling traffic and power outages in Orange County and revived jitters among residents of South County’s coastal communities already heavily damaged by earlier fires and mudslides.

But in Laguna Beach, hillsides ravaged in the Oct. 27 fire were holding up pretty well, according to Bill Reiter, public works operations manager for the county’s Environmental Management Agency.

Reiter’s office was coordinating the efforts of about 50 workers--including 24 prison inmates--on hand to monitor the situation and help shore up hillsides in case of mudslides.

In Malibu, however, the mudslides brought chaos and confrontations.

Several people who did not want to leave “had to be removed forcibly,” said Capt. Scott Smith of the Los Angeles County Fire Department.

One who left willingly was Greg Powers, whose beachfront house was invaded by tree trunks, shrubbery and almost four feet of mud and water. Powers said his Jeep was carried away by the torrent that hit his home about 3 p.m.

“I think I might move,” he said. “I’m tired of this. First it was the fires, then the earthquake, now this.”

As Powers surveyed the damage, he carried his two yowling cats around with him in a soggy cardboard pet carrier. “They’re kind of upset,” he said.

Monique Marti, who lives several houses away, said that more than 20 years ago, “the same thing happened.” She said she probably would spend the night with friends in Santa Monica.

“But you hate to go away from your home,” she said. “Because you don’t know what it will look like when you get back.”

Sharon Sandler returned from work Monday night to find her house filled with four feet of mud. “The bedroom has been washed away into the ocean,” she said. “It was like a river running through it.”

The water spilled off her back porch like a waterfall, splattering down into storm-driven waves that swirled around the pilings supporting her home. Although some of the sand around the pilings was washing away, all the homes appeared to be standing fast Monday night.

Vera Smith slogged her way to safety after her Mercedes-Benz was trapped in a mudflow near Big Rock Drive.

“As I looked to make the next curve, there was this huge bank of mud coming toward me,” she told a KABC-TV crew. “Unbelievable, unbelievable--things you see in the movies. And it was happening to me.”

Above Malibu, basketball-size rocks crashed down onto Old Topanga Canyon Road, and sheets of mud and gravel covered stretches of the pavement. The persistent rain was beginning to warp wooden signs thanking firefighters for their efforts during the hellish fires that burned through Topanga Canyon last fall.

In Altadena, mud, rocks and debris from about 600 acres burned in last fall’s fire slid onto Pasadena Glen Road during a cloudburst, isolating about 20 hillside homes and damaging some of them. Most of the residents already had fled or were away at work, but about a dozen were cut off as the mudslides continued to threaten their houses.

After about an hour, county firefighters slogged through mud up to four feet deep to reach the stranded people and escort them to safety. There were no reports of injury.

Curtis Brack, a meteorologist with WeatherData Inc., said the heavy rain should taper off well before dawn today, with a few showers--and possibly some more thundershowers--predicted until about noon.

“There should be partial clearing by the afternoon as the storm system continues moving inland,” he said. “After that, it looks like it should be pretty dry for the rest of the week.”

Times staff writers Mike Carlson, Nieson Himmel, Shawn Hubler, Bob Pool and Jeannette Regalado contributed to this story.

* DISASTER MODE: Laguna residents were prepared in face of storms. B1

Wind Damage

Tornado-like winds stormed through Irvine on Monday, causing minor damage in a wide swath to the Tustin Marine Corps Air Station.

1. Winds begin, 6-6:30 p.m.

2. Windows shattered, trees blown down

3. Trees uprooted

4. Traffic signal blown down

5. Windows shattered, roofs damaged

6. Trees uprooted, roofs damaged on Hale Avenue

Stormy Monday

A blustery storm dropped nearly an inch of rain in some parts of Orange County on Monday but did not bring this season’s lagging rainfall total into line with the normal amount. Monday’s rain in inches, midnight to 4 p.m.: City: Inches Santa Ana: 1.30 Irvine: .88 Lake Forest: .83 San Juan Capistrano: .80 Anaheim: .72 Newport Beach: .71 Laguna Beach: .57 Dana Point: .26 *

YEAR-TO-DATE RAIN

Total county rainfall for this season, which began July 1, is still more than two inches below normal and only about one-third of last year. Santa Ana readings, as of 4 p.m. Monday: Period: Inches Season: 5.16 Last year: 16.93 Normal: 7.52 Source: WeatherData Inc.

Researched by CAROLINE LEMKE / Los Angeles Times