Coming Storm Prompts Calif. Evacuations

Updated at 3:45 p.m. ET

Los Angeles County sheriff's deputies have begun going door-to-door in foothill neighborhoods to urge hundreds of residents to obey evacuation orders as another powerful Pacific storm heads into California.

In the upper reaches of suburban La Canada Flintridge, most residents complied Wednesday morning but some have declined to go.

The foothill communities are directly below towering slopes of the San Gabriel Mountains that were burned bare by a 250-square-mile wildfire last summer.

Authorities fear that huge flows of storm runoff laden with debris could overflow flood-control catch basins and plow into homes.

The third storm of the week is expected to bring more heavy rain and fierce winds from midday into evening.

No flooding is reported there yet - but further west, a car-sized boulder dropped from a hillside onto the 101 freeway near Hollywood, blocking an offramp.

CBS News correspondent Hattie Kauffman reports that officials are warning the residents they may not be allowed to return to their homes for as long as a week.

Even for many Californians not under evacuation orders, Kauffman says this could shape up to be one of the worst weeks of weather the state has seen in a decade.

The foothills have received almost 5 inches of rain since Sunday and Wednesday's storm is predicted to drop 4 to 8 inches on the area, Department of Public Works Director Gail Farber said.

County Fire Chief P. Michael Freeman begged residents to heed their evacuations orders. He said public safety officials are racing against Mother Nature.

"And if she wins the race there's no way we can assure that firefighters, as well-equipped and as trained as they are, will be able to get into your neighborhood and make rescues," Freeman said.

In the foothills of La Canada Flintridge, just north of Los Angeles, County Public Works crews used bulldozers and shovels to move mud out of cul-de-sacs. The storm left fist-sized rocks strewn across a winding, canyon road.

One resident, Gary Stibal, had lined his backyard with sandbags a couple of feet high to divert the floodwater. His hard work kept out the rocks and debris on Tuesday, but Stibal, whose home was threatened by one of last year's wildfires, said he was worried that water from the third storm would reach his home.

"The ground is really saturated right now from the two storms we had come through yesterday and today, so I'm really concerned," he said as he surveyed his work.

The storm did serious damage Tuesday, crushing a woman to death with a fallen tree, flooding coastal neighborhoods and leaving thousands without power as lightning and tornados surged ashore with fierce winds in Santa Barbara, Los Angeles County beach towns and areas of Orange and San Diego counties.

San Diego sheriff's Lt. Mike Munsey said a woman was killed when a eucalyptus tree with a 10-foot diameter trunk crushed her trailer and a neighbor's in a mobile home park near El Cajon. On Monday, a man was killed near Bakersfield when a tree fell on his home.

In San Pedro, a working class neighborhood near the Port of Los Angeles, several blocks were flooded with about six feet of water when storm drains clogged with debris. Police said 16 people were displaced from flooded homes.

Jerry Bazan spent the afternoon sweeping several inches of water out of his living room, where toys, sodden clothing and furniture were strewn about and a thick layer of mud coated the floor. The water rose quickly in his apartment and some of it was contaminated with sewage.

"It was a heavy downpour, and the drainage system was clogged," he said. "There was nowhere for the water to go, and it just rose up."

A small tornado flipped a parked SUV onto its side and blew out windows in Seal Beach.

Flash flood watches remained for areas of Santa Barbara, Ventura and Los Angeles counties where wildfires in 2008 and last year stripped hillsides down to bare, black earth.

A strong jet stream was sending the line of storms ashore from the Pacific Ocean, with the wet weather expected to continue through Thursday.