A wildfire raged through some of Los Angeles’s upscale neighbourhoods on Tuesday, prompting city officials to chide wealthy evacuees to remember to tell their housekeepers and gardeners not to enter the danger zone.

Wind-driven blazes were burning largely uncontrolled in tinder-dry areas around Los Angeles as well as further north in California’s wine country. Firefighters were battling to try to save thousands of imperilled homes as thousands of residents fled the area.

Los Angeles officials reminded wealthy evacuees to alert their service employees of the danger in light of news reports that several turned up for work at some of the 10,000 homes and businesses under smoky skies in the mandatory evacuation zone.

“I want to encourage people to be reaching out to anybody who may be showing up at their home and urge them to stay away,” council member Mike Bonin told a news conference on Tuesday morning.

The brush fire that broke out early on Monday near the Getty Centre art museum on the city’s West Side grew about 40 acres overnight to 658 acres, mayor Eric Garcetti told a news conference.

“That’s a good sign, actually, that it didn’t grow by more,” he said. Eight homes have been destroyed so far.

Across the state, hundreds of thousands of people were left in the dark as power companies cut off electricity to try to prevent more fires from being sparked by snapped cabling in the brushland.

Los Angeles Lakers basketball great LeBron James, Terminator actor and former California governor Arnold Schwarzenegger, as well other celebrities, tweeted that they had been forced to evacuate their homes.

Weather forecasters say there could be worse to come, with the National Weather Service (NWS) predicting gusting winds in the mountains around Los Angeles, where planes have been dousing the fire from the air.

Until at least Wednesday, in the bone-dry wine country about 113km north of San Francisco, winds will hit up to 101kmph in the mountain areas and 56kmph in the valleys and coast around where the Kincade Fire, the state’s biggest, is burning, he said.

As of early Tuesday, the Kincade fire had scorched more than 75,000 acres, destroyed 123 homes and other structures and was 15 per cent contained as it burned across parts of Sonoma County's wine country, state fire officials said.