At least 200 people were evacuated across northern California as the risk of damaging mudslides grew. A storm dumped what could be six inches of rain over the area, according to a dispatcher for the California Highway Patrol.
Some 300,000 people were without power on Wednesday morning. Wind gusts reached 60 mph.
Most of the rain fell in Napa and Sonoma counties, north of San Francisco. Santa Barbara saw minor flooding, and several small mudslides or rockslides blocked local roads in Santa Barbara, Los Angeles and San Bernardino counties.
The risk of damaging mudslides is highest in mountain communities burned during last year's wildfires. There is no vegetation to hold back rushing water and mud.
Residents in the San Bernardino Mountains were sandbagging as a precaution.
The storm marks an early start to California's winter season.
On a positive note, the rain prompted at least some forest officials to ease fire restrictions.
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