The National Weather Service has also issued a high-surf advisory and a coastal flood warning for Los Angeles County beaches. Meteorologist Jamie Meier predicted waves as high as 20 feet and winds as strong as 60 mph, compared with 6- to 10-foot surf and peak gusts of 30 mph Tuesday.

Officials issued a flash flood watch and thunderstorm warning for the region, forecasting sustained rainfall and fierce winds. Forecasters say the strongest drenching could occur Thursday, with up to 3 inches of rain and the possible return of tornado-like conditions.

[Updated at 1:53 p.m.: The California Highway Patrol closed Interstate 5 at the Grapevine because of snow. The Cajon Pass remained open, but motorists reported extremely poor visibility on the mountain roadway that provides access to Victorville, Barstow and eventually Las Vegas.]

According to the National Weather Service, today's storm -- the third in as three days -- is expected to dump 1 to 2 inches of rain in the L.A. basin and valley areas and 3 to 4 inches in foothill and mountain areas.

In anticipation of mudslides, the Los Angeles Police Department issued evacuation orders in the northeastern San Fernando Valley, where residents in 262 homes were supposed to leave by 9 a.m.

"We're asking you to please cooperate," Los Angeles Mayor Antonio Villaraigosa said at a news conference at Fire Station 81 in Panorama City. "There's too many people not heeding advice."

Also, this morning authorities planned to order the evacuation of about 500 homes in La Crescenta, La Cañada Flintridge and Acton. The evacuations were to begin at 9 a.m. and be completed by 1 p.m. A full list of the addresses of homes affected by the evacuation is available on the Coordinated Agency Recovery Effort (CARE) website. Officials said the evacuations will likely remain in effect through Monday morning.

Glendale ordered more than 300 homes evacuated.

[Updated at 12:20 p.m.: Two Southwest Airlines Boeing 737s were struck by lightning during their flights today but landed safely at Bob Hope Airport in Burbank. One flight attendant who complained of pain in her arm was taken to a hospital for examination, authorities said.

The airliners, which were flying to Burbank from Sacramento and Oakland, landed at 9:38 a.m. and 9:57 a.m., said Marilee McInnis, a spokeswoman for Southwest Airlines. Both planes were taken out of service to check for possible damage.

Warning that lives could be at risk, Villaraigosa pleaded today with residents in mudslide-prone foothill areas to evacuate and said the city could be looking at a “La Conchita situation” if the intense rains move in as forecast. Ten people were killed in La Conchita in 2005 when the hillsides above the small Ventura County community came down.

Joined at a late-morning news conference by Police Chief Charlie Beck and Fire Chief Millage Peaks, the mayor said that hillside communities from Glendale to Sunland were at the greatest risk.

“We’re asking you to work with us on this,” the mayor said.]

In the quiet and fog-covered La Cañada-Flintridge neighborhood of Paradise Valley, Debby Mahoney, 57, stood in front of her Bristow Drive home during one of the brief interludes from the heavy rain.

Two Los Angeles County sheriff's deputies approached her and one of them carried a form. But Mahoney, a business manager, told them she had already signed the form, which confirmed her decision not to heed the evacuation order.

She reasoned she would be safe from flooding or mudslides since her home is located on a hill and one of the many debris basins is beneath the hill.

“It’s not logical that gravity goes up hill," she said.

Months earlier, she had evacuated when the Station fire brought raging flames feet away from her home. But this time she plans to stay at home with her four cats. “A hotel room with four cats; what a mess,” Mahoney said. “We have a generator and lots of food; there’s no reason to leave.”

So far, two fatalities have been blamed on the series of storms. An El Cajon woman was crushed to death Tuesday afternoon when the passing storm uprooted a tree, which fell on her. On Monday night, a 100-foot tree crashed to the ground in Frazier Park, crushing a man and his home.



Tuesday's storm was brief and intense, as coastal areas were subjected to hail, thunder, lightning and powerful winds for about two hours before giving way to sunshine and rainbows.



The National Weather Service recorded at least one tornado, four waterspouts and gale-force winds of up to 80 mph as the fast-moving storm swept through the Los Angeles Basin. Some witnesses said they spotted tornadoes in Costa Mesa and Goleta.



The force of the storm ripped several roofs off buildings, shattered windows and displaced about 40 people in San Pedro. Chest-high water gushed through the streets so quickly that it stranded drivers on the 710 Freeway in Long Beach and swallowed cars in parts of Belmont Heights.



Rescue crews spent hours in Long Beach and Orange County plucking residents out of flooded cars and homes.



Lightning struck the ConocoPhillips refinery in Wilmington, sparking a small fire in one of the stacks. Wind swept through Costa Mesa and took chunks of several buildings with it.



A possible tornado "touched down on the building across from us and ripped off the paper and insulation and flung it into the street, landed into our building and ripped the skylight off," said Charlie Rose, 29, publisher of independent music magazine L.A. Record, whose office is in Costa Mesa at Whittier Avenue and 17th Street.



At Peter's Landing Marina in Huntington Harbor, manager Scott Seaton watched through the window as a "cyclone" came over the building and touched down in the marina. At one point, Seaton watched it pick up a 40-foot catamaran, twirl it several feet in the air, then drop it on top of another boat.



"It was just amazing watching that thing dance up in the air," Seaton said. "As quick as it came, it was gone. I can't even imagine seeing a monster one because this thing seemed so powerful. ... It was just unbelievable."



Chad Zarndt said he felt "violent shaking. I've never seen anything like this here in O.C."



Nearby, the tornado lifted a parked SUV and sent it crashing to the ground, shattering windows.



In Long Beach, the problem was rising water.



Isaac Chavira, 25, who lives in a two-bedroom, ground-floor apartment at 8th Street and Bennett Avenue, said he had just put his 19-month-old daughter down for a nap around noon when brown muddy water started seeping through under door. He peered out the window and saw water and debris running down the street "like a river."



Eventually, the water reached his shins.



"I kind of panicked," he said. He opened the windows and yelled, "What do I do?" to his neighbors.

-- Ann M. Simmons in La Cañada Flintridge and Richard Winton in Los Angeles

Map image: National Weather Service

View our storm coverage on an interactive map , which we will be updating throughout the evening.

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