Weather service warns drenching rain, flash flooding and landslides

(CNN) – A strong storm is expected to bring drenching rain and the threat of flash flooding and landslides to Southern California late Friday and through the weekend, the National Weather Service warned Thursday.

Flood watches affecting more than 20 million people have been posted for the southern portion of the state, including Los Angeles and San Diego. The widespread watches extend into the foothills of the southern Sierra.

The most rainfall is expected to hit Friday evening, with up to 6 inches possible in just six hours along the coast and in the valleys of Santa Barbara, Ventura and Los Angeles counties.

“The storm looks to be the strongest storm to hit southwest California this season. It is likely the strongest within the last six years and possibly even as far back as December 2004 or January 1995,” the National Weather Service in Los Angeles said.

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