Winter’s First Major Storm Drenches O.C. : Weather: The fire-ravaged areas of Laguna Beach are put on mudslide alert as more rain is forecast.

A potent storm from the Gulf of Alaska dumped substantial rain and snow on Southern California on Tuesday, snarling traffic with accidents and flooded intersections, blocking mountain passes with wind-whipped snowdrifts and prompting mudslide warnings below fire-scarred hillsides.

More than 1 1/2 inches of rain fell in some foothill communities by nightfall, with nearly a foot of new snow reported at some mountain resorts. Forecasters said those totals could double before the complex weather system finally moves out of the Southland sometime Thursday afternoon.

Orange County residents sloshed their way to their first official day of work this year through slippery freeways, many snarled with traffic backups. At one point Tuesday morning, California Highway Patrol officials in South Orange County reported about half a dozen rain-related accidents in a 30-minute interval.

“Around 10 and 11 a.m., it really got crazy around here,” CHP spokesman Bruce Lian said.

A tractor-trailer collision tied up traffic on the southbound Interstate 5 north of El Toro Road, closing two lanes for about an hour. The crash occurred when Juan Francisco Tovar, 26, of Mission Viejo was “going too fast in the rain and lost control” on an on-ramp, crashing into the truck, Lian said.

Tovar was taken to Mission Community Hospital. The truck driver was unhurt.

The first major storm of the winter struck Southern California about 2 a.m. Tuesday, and by dawn the steady rainfall in the coastal valleys was accompanied by a heavy frosting of snow in the San Gabriel and San Bernardino mountains.

Interstate 5--California’s principal north-south highway--was closed by heavy snow and gusting winds near the Tejon Pass at about 8 a.m. Officials said it took Caltrans crews more than three hours to reopen the roadway. There were concerns that more snow during the night could again block the pass through the Tehachapis 75 miles north of Los Angeles, before dawn today.

About three inches of snow fell in Palmdale and in other high-lying areas of the Antelope Valley. Roads there remained open, but the commuter drive slowed to a crawl.

Little snow fell on Interstate 15--which traverses the San Bernardino Mountains through Cajon Pass, 20 miles north of San Bernardino--but southbound lanes in the pass were closed temporarily by a crash involving two big-rig trucks and three other vehicles. The California Highway Patrol said that because of high winds and fog in the pass, high-profile vehicles were advised to use alternate routes.

In the Los Angeles metropolitan area, the problem was rain, not snow.

The National Weather Service issued a flash-flood warning of possible mudslides in the Topanga Canyon, Malibu, Altadena and Laguna Beach communities areas stripped of soil-holding vegetation during disastrous brush fires in the fall of 1993.

In Laguna Beach, officials monitored the weather throughout the day watching for the first signs of mudslides in the hills denuded by fire last year. Municipal services crews stood by, and firefighters were prepared to reopen the city’s storm operations center.

“We’re ready,” said Wade Brown, city parks and buildings manager.

By nightfall Tuesday, no slides had been reported, but forecasters said additional rain was expected before dawn. Occasional moderate showers were forecast for today, with more heavy rain tonight.

Lifeguards at Newport Beach also assigned an additional rescue team member to remain on call throughout the night as a southeast wind churned the surf, Lt. Eric Bauer said.

Meanwhile, morning commuters faced a triple threat: A wave of back-to-work traffic after an extended holiday weekend; flooded intersections in low-lying areas that stalled a number of cars and a rash of traffic accidents on the rain-slick pavement.

The CHP said it logged more than 250 accident calls on Los Angeles County freeways between 8 a.m. and noon--nearly four times the usual number during dry weather.

The accidents, for the most part, were minor, with few serious injuries reported. But some of the mishaps disabled large trucks, and the sprawled wreckage contributed to the traffic tie-ups.

A pressurized tanker truck carrying liquid oxygen crashed in the westbound lanes of the Foothill Freeway in downtown Pasadena at 6 a.m. Tuesday. The tank ruptured, and the spewing gas forced closure of several traffic lanes.

Several hours later, a big rig jackknifed into the center divider of the same freeway in Irwindale, blocking traffic until the debris could be cleared. Another big truck jackknifed across several lanes of traffic on the Golden State Freeway in the Sylmar area, creating a tie-up there.

The core of the storm passed through Orange County from about 5 to 10 a.m., leaving skies clear by noon. Highs were in the upper 50s and lower 60s.

A 60% chance of rain is predicted today, with highs in the mid 50s to lower 60s, and a 40% chance is predicted for Thursday.

“The rain helps us because it means people won’t be watering their lawns or washing their cars. It takes some of the impact off of the local agencies,” said Bob Muir, a spokesman for the Metropolitan Water District. “It’s a nice way to bring in the year.”

Times staff writers Henry Chu and Jeanette DeSantis in the San Fernando Valley, Tom Gorman in San Bernardino and Debbie Kong in Orange County contributed to this story.

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Rainy Beginnings

The first week of the new year brought stormy weather that is not expected to subside until Thursday afternoon. A 60% chance of rain is expected through tonight, decreasing to a 40% chance of showers Thursday morning. Tuesday’s rain, from midnight to 4 p.m. City: Inches Santa Ana: 0.30 Anaheim: 0.38 Newport Beach: 0.33 Lake Forest: 0.10 Dana Point: 0.32 Laguna Beach: 0.40 ***

YEAR-TO-DATE RAIN

Santa Ana readings, as of 4 p.m. Tuesday, for rain season beginning July 1. Period: Inches Season: 2.25 Last year: 1.95 Normal: 3.90 Source: WeatherData Inc.