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LOS ANGELES, March 22 (Reuters) - Heavy rains in Southern California on Thursday threatened to cause dangerous mudslides in the hills northwest of Los Angeles, after thousands of people evacuated their homes in a region where slides killed 21 people in January.
Officials in Ventura County, northwest of Los Angeles, ordered dozens of people to evacuate their homes near areas where last year's wildfires burned away grass and shrubs that normally hold soil in place and baked a hardened level of earth that keeps precipitation near the surface.
So far more than 60,000 residents of Ventura and Santa Barbara counties have been asked or ordered to leave their homes since the rains began.
The storm could drench mountainsides with up to 10 inches (25 cm) of rain before it weakens on Thursday night, said National Weather Service specialist Stuart Seto.
"The storm has a lot of intensity behind it and has the potential to be life-threatening," said Amber Anderson, a spokeswoman for the Santa Barbara Fire Department. "The public, for the most part, has heeded the warnings for evacuations."
In January, heavy rainfall caused a mudslide that killed 21 people and destroyed or damaged hundreds of homes, mostly around the wealthy Montecito enclave, which is about 85 miles (137 km) northwest of Los Angeles and is home to celebrities such as Oprah Winfrey and Ellen DeGeneres.
The latest storm flooded some streets in Montecito but has not resulted in major damage, Anderson said.
This storm, with combined moisture flows from Hawaii and southern tropical regions, was more intense than January's rains in Southern California, the National Weather Service's Seto said.
The Rocky Butte area in San Luis Obispo County, north of Santa Barbara, has already received nearly 9 inches (23 cm) of rain, he said.
Several roadways in coastal counties northwest of Los Angeles have been flooded and there have been a number of car crashes on slick roadways, but no deaths, California Highway Patrol spokesman Danny Maher told Reuters by phone.
As rains soaked parts of California, the East Coast was digging out from the fourth major snowstorm this month, which closed schools, grounded flights and halted bus and train service across the region. Two people died in separate traffic crashes, local media reported. (Additional reporting by Brendan O'Brien in Milwaukee; editing by Larry King and Dan Grebler)