Heavy rainstorms drenched California for a third day Friday, stranding motorists in flooded desert creeks, swelling surf that washed away part of a Malibu home and shrouding mountains with snow that contributed to a bus crash.

In Los Angeles, on the day that mandatory water rationing took effect, rainfall at the Civic Center totaled 3.71 inches by 9 a.m., making the storm the biggest to hit the drought-parched region in at least three and possibly five years.Weather service meteorologist Mark Rochin said the storm that hit Wednesday also would probably be the wettest in a series of weak weather troughs expected to cross Southern California over the weekend, probably on Sunday and again about Tuesday.

So much rain in so little time contributed to slides of mud and rocks that closed the Angeles Crest Highway near Clear Creek Vista, north of Pasadena, for most of the day and northbound lanes of Highway 101 to the Santa Barbara County line in the early morning.

High tides accompanying the storm as it swept in from the Pacific also loosened the foundations of a Malibu beachfront home, allowing about a third of the house to break away. The home was condemned and a $1 million loss declared.

Surf lapping over a retaining wall also posed a threat to three other homes in the high-priced beachfront community.

The rain also caused routine wet-weather havoc on freeways, including a 10-car pile-up on I-5 near San Juan Capistrano and a four-hour morning rush tie-up on the Hollywood Freeway after a tractor trailer skidded and lost a load of wooden pallets.

In the mountains, more than 2 feet of snow had fallen and another 4 to 8 inches were expected by the end of the day at levels at low as 4, 550 feet in the northern Sierra.

Heavy snow falling in the Sierra near South Lake Tahoe contributed to a Greyhound bus crash on Highway 50 early Friday. The bus skidded on a curve and careened through a guard rail, but all 17 people aboard escaped serious injury, California Highway Patrol officials said.