Flash flood warnings were announced in parts of California early on Thursday amid reports of a possible tornado in the southern half of the state.
Heavy rain and thunderstorms were expected to continue today with widespread flooding risk including in Los Angeles, Long Beach and Pomona, the National Weather Service (NWS) said.
A possible tornado was reported overnight in Grover Beach, southern California after warnings were issued late Wednesday.
The threat of mudslides remains high from the storm, which unleashed historic amounts of rain this week, leaving the ground saturated.
At least nine people have been killed from falling trees, car crashes, and being swept away in raging waters.
Community organisers told The Independent on Wednesday that Los Angeles’ storm response for the city’s large homeless population was “abysmal” and accused authorities of telling “bold-faced-lies”.