LOS ANGELES (AP) _ Rain began pelting parts of Southern California early Friday as a fierce winter storm from the Pacific Northwest moved in ahead of schedule, triggering fears that recent wildfires may gave left the region susceptible to flash flooding.
Southern California has had a very dry rainy season, and it will be the first time since April 2006 that so much rain has fallen from a single storm, said Stuart Seto, chief weather specialist with the National Weather Service in Oxnard.
The weather service issued a flash flood watch for coastal and mountain areas through Friday afternoon. The forecast called for winds gusting to about 30 mph ahead of a storm front that could drop up to an inch of rain in urban areas and up to 3 inches in the mountains, Seto said.
The weather service also issued a high wind warning for the mountain areas and in the Antelope Valley, north Los Angeles county. The winds were expected to blow 30- to 45 mph, with potentially damaging gusts of up to 60 mph, said meteorologist Todd Hall.
Areas denuded by recent fires were a special concern. Wildfires have stripped vegetation from thousands of acres of land now susceptible to excessive runoff and erosion.
``It doesn't take much to set off those mud and debris flows,'' Seto said.
Before the storm hit, a few thousands people were evacuated on Thursday from three Orange County canyons burned bare by wildfires earlier in the year. Orange County sheriff's patrol cars broadcast the warning through loudspeakers to residents of Modjeska, Williams and Silverado canyons.
In Los Angeles County, work crews sandbagged hillsides in Griffith Park, where about 1,200 acres _ almost 2 square miles _ were scorched in May. Other work was under way in Malibu, where a wildfire destroyed 53 homes in November.
In Washington state, meanwhile, officials partially reopened a section of Interstate 5 that had been swamped by floodwater and closed for three days after a previous storm system crashed through the region.
A 20-mile stretch of the freeway near Centralia was shut down Monday night, when the swollen Chehalis River made the route too dangerous to use. The interstate eventually was covered by as much as 10 feet of water, officials said.
By Thursday night, receding floodwater and repair work allowed the state to open one northbound and one southbound lane, with traffic initially limited to freight haulers.