LA CANADA FLINTRIDGE, Calif. (AP) -- Steady rain fell Thursday on saturated Southern California as the fourth Pacific storm in a week came ashore, triggering dire warnings by authorities that mud flows were likely in foothill communities and residents of endangered homes should obey evacuation orders.

Travel snarls mounted as a major highway was closed by snow and strong winds forced cancellation of dozens of flights at several airports.

The siege of storms has led to several deaths statewide and flooding in urban areas and on freeways.

Officials appeared concerned the lack of massive debris flows from wildfire burn areas was misleading for residents.

"It's time to roll, it's time to evacuate," said Los Angeles County Public Works Director Gail Farber.

County Fire Chief Deputy John Tripp bluntly warned that significant debris flows were likely and probably would block potential
rescue attempts.

"For those people that are still in the homes and are in those areas of threat, it's very likely we will not be able to reach you," he said.

In the upper reaches of suburban La Canada Flintridge, where mountainsides rise sharply from the backyards of homes, authorities put pink ribbons on the mailboxes of residents who stayed behind so they would know where to search in the event of a catastrophe.

One person who didn't leave was Delos Tucker, a retired geologist who has lived in the community since the homes were built in 1962.

"I'm just gambling it's not going to happen," he said. "Let's hope I'm right."

As an overnight lull gave way to more rain at midmorning, public works crews shoveled mud from yards, driveways and gutters along Ocean View Boulevard in suburban La Canada Flintridge. The neighborhood was otherwise all but deserted, with newspaper and mail deliveries cut off.

The county's extensive flood-control system was working, but many of the basins designed to catch debris-laden runoff from fire-scarred mountains were full and evacuations remained necessary, Farber said.

The basins are located on streams and other water courses emerging from the mountains to intercept surges of mud, boulders and other debris while allowing water to flow into open channels and underground storm drains that empty into the ocean.

"We can thank a measure of luck and the flood control system ... for working so well, however we can't keep counting on luck forever," said Los Angeles County sheriff's Chief Neil Tyler.

The arrival of the new storm system shut down Interstate 5 in the snowy Tehachapi Mountains north of Los Angeles for the second day in a row, interrupting travel on one of state's major arteries.

Southwest Airlines canceled dozens of flights at San Diego's Lindbergh Field due to strong winds.

Since late Sunday, as much as 6 inches of rain had fallen in the mountains of Los Angeles County and more than 3 inches downtown, according to the National Weather Service.

Thursday's storm was expected to drop 2 inches to 4 inches of rain in the drenched foothills and mountains, with potentially strong downpours and intense rain rates, said NWS meteorologist Eric Boldt.

Rain was expected to taper off by night, followed by showers on Friday and a dry weekend.

The major area of concern has been foothill communities along the perimeter of the San Gabriel Mountains, where a summer wildfire denuded 250 square miles of steep slopes northeast of Los Angeles.

The number of homes under evacuation orders has grown to more than 1,200 since the beginning of the week. Estimates of compliance have ranged up to 75 percent in some jurisdictions but down to 40 percent elsewhere.

Tucker acknowledged that with catch basins filled with mud, water and debris, things could become difficult. But he said he had seen regrowth in the fire-scarred hills and believed it would hold soil in place.

At one point he left to bring his wife back from a visit to their daughter and defied a deputy who threatened to arrest him if he returned to his house. The deputy didn't follow through on the threat, and Tucker was not upset by the incident.

"They have to play it super safe," he said. "Obviously there is danger of a major mudflow coming down from the canyon."

Despite the statewide extent of the storms, the number of deaths remained low. Two people were killed by falling trees, and police in Newman were searching for the body of a man who tried to drive across a flooded road.

In San Jose, a man died after falling 30 feet from the side of a freeway after he got out of a car that spun out in the rain and then jumped out of the path of an out-of-control car.

In San Diego, the Border Patrol said three people were rescued and treated for hypothermia after being swept away while trying to cross the storm-swollen Tijuana River from Mexico.

California State University, Long Beach, remained closed after some buildings flooded Wednesday.

The weather also forced cancellation of horse racing at Santa Anita Park in Arcadia and postponement of the second round of the Bob Hope Classic golf tournament near Palm Springs.

Sea World in San Diego was also closed due to severe weather.

Air travel through Phoenix was disrupted by severe weather as the storms moved eastward through Arizona.
------
Associated Press Writer Elliot Spagat in San Diego contributed to this report.

Fires, govt. bankruptcy, social upheaval and mudslides....Man! Cali has just had a rough year! Sure hope the rains cause less havoc than feared!