A funnel cloud begins to form in Sacramento, Calif., Monday. (AP photo)

At least five people have been killed as rainstorms continue across California, spawning tornadoes, landslides and avalanches.

The storm system is expected to bring at least another 25 millimetres of rain to Southern California before moving out of the region by Wednesday afternoon, say weather officials.

Two tornadoes hit the Sacramento area Monday afternoon, uprooting trees and fences and ripping off roofs. Severe thunderstorms and hail pounded the northern part of the state.

Part of the Hollywood Freeway in Los Angeles was shut down Monday as emergency crews pumped out as much as 1.5 metres of water. California Highway patrol reported more than 300 crashes in 14 hours, compared with a usual rate of about 50 crashes.

5 killed by mudslides, flooding


California backyard pool on the brink.

Southern California has been drenched by a series of storms that began Friday, dropping more than 165 millimetres of rain on downtown Los Angeles. At least five people have been killed in separate storm-related incidents.

A 63-year-old man was killed Monday when a mountain of mud slammed into his home in the San Fernando Valley, while a 16-year-old girl died when a boulder came loose from a mountain and crashed into her bedroom near Irvine.

In San Bernardino, a father of four died when his car skidded off the road and down an embankment.

On Sunday, a repair worker died when he fell into a nine-metre-deep sinkhole in Los Angeles's Sun Valley, and a woman died in an avalanche while skiing in northern California near Lake Tahoe.

There have been some narrow escapes from the water and mud.

Rescue workers pulled three people alive from about three metres of mud that flowed into a townhouse in Hacienda Heights, just east of Los Angeles. The slide forced about 30 other people in the townhouse complex to flee.

In another affected area, a 39-year-old woman was rescued after being trapped for hours in her bathroom, waist deep in mud and debris.