Soaring temperatures are hindering crew efforts to contain the fires that began last week near Big Sur and in northern Los Angeles County and temperatures are expected to climb heading into the weekend.

The majority of some 20,000 people forced from their homes by a wildfire that exploded during the weekend were told they could return home Monday night, though an army of firefighters continued battling flames in the rugged hills and canyons northwest of Los Angeles.

A massive wildfire destroyed at least 18 homes and threatened 1,500 more Sunday as flames churned through tinder-dry canyons north of Los Angeles where authorities found a burned body in a neighbourhood.

California bore down Saturday against the continuing heat and wildfires that have forced the evacuations of hundreds of homes as red-flag warnings of extreme fire danger predicted gusty winds and scorching, dry air.