The weather forecast has been upgraded to a severe weather warning for parts of southern California and some parts of the San Joaquin Valley, with winds of up to 40 mph and rain likely.
Heavy rain is expected to continue across much of the state Friday, but some areas could see little or no rain.
The weather is expected in the mountains north of Fresno and Kern counties and in the central Sierra Nevada.
The National Weather Service has updated its severe weather watch for Southern California.
The agency has updated to a tropical storm warning for the Central Valley and the San Francisco Bay area.
The forecast is more severe than the one issued Friday morning.
The storm could also bring heavy rainfall to the Los Angeles area, with up to 8 inches of rain possible in the city, according to the National Weather Services.
The National Hurricane Center says the storm is expected at a Category 4 or 5 strength.