Evacuation warnings are in place for parts of Southern California as an incoming storm could bring potential mudslides and debris flows to burn scar areas, according to county officials. "Anyone in these areas should be ready to leave at a moment's notice," Los Angeles County officials said in a statement.

LATEST Nov. 13 12:20 p.m. A bomb cyclone off the coast of California was bringing heavy rain and winds to the northern part of the state Thursday, according to the National Weather Service. Dalton Behringer, a meteorologist at the weather service, said the current storm front dropped about 19 millibars within 24 hours.

A potent midweek storm is expected to bring widespread rain, colder temperatures and gusty winds across the Bay Area and portions of the Central Coast beginning Wednesday, forecasters said Tuesday.

An unusually strong storm system called an atmospheric river was dousing Southern California on Saturday, prompting flood warnings in areas of coastal Los Angeles County that recently were ravaged by wildfires.

A minor, 3.5-magnitude earthquake struck in the San Francisco Bay Area on Thursday, according to the United States Geological Survey. The temblor happened at 12:41 p.m. Pacific time about 2 miles south of Vallejo, Calif., data from the agency shows. U.S.G.S. data earlier reported that the magnitude was 3.6.