Heavy rain overnight north of San Francisco, particularly in the Napa and Sonoma wine regions, caused several rivers to overflow, forcing the evacuation of at-risk neighborhoods, said Dale Chessey, an emergency services spokesman.

The storm also triggered landslides, officials said.

Six emergency shelters opened in Napa and Sonoma, the local Red Cross chapter said. About 200 people were being evacuated in Napa alone.

There were not reported victims, Chessey said.