Crews faced hot dry "devil winds" as they battled two giant wildfires raging at opposite ends of California, including a blaze in the north that is now one of the deadliest and most destructive in the state's history.
At least 23 people have been killed by the Camp Fire that broke out on Thursday northeast of Sacramento and consumed much of the mountain town of Paradise.
More than 100 were reported missing. Hundreds of miles to the south, at least two people died in the Woolsey conflagration threatening the wealthy beach community of Malibu, near Los Angeles.
The Camp Fire burned down more than 6700 homes and businesses in Paradise, more structures than any other California wildfire on record, and the death toll, which could rise, also made it one of the deadliest.
Only the Griffith Park Fire in 1933 and Tunnel Fire in 1991 have claimed more lives.
Several of the bodies discovered earlier this week were found in or near burned out cars, police have said.
The flames descended on Paradise so fast that many people were forced to abandon their vehicles and run for their lives down the only road through the mountain town.
More than 110 people were reported missing in the fire-scorched area, said a spokeswoman for the Butte County Sheriff's office, who declined further comment.
As of Sunday, the Camp Fire had blackened more than 109,000 acres at the edge of the Plumas National Forest. Crews had cut containment lines around about 25 percent of the blaze.
Winds of up to 64km/h were forecast to blow across the area today.
Gusts of up to 113km/h the so-called Santa Ana "devil wind," were expected in the Los Angeles area where crews are fighting the Woolsey Fire.
"This is getting bad," said meteorologist Marc Chenard, with the National Weather Service's Weather Prediction Center in College Park, Maryland. "It's nothing but bad news."
The air-masses blowing across the western US deserts, including Death Valley toward the coast are expected to bring the sustained high winds at least through Tuesday, he said.
The Woolsey Fire doubled in size from Friday night into Sunday threatening thousands of homes after triggering mandatory evacuation orders for a quarter million people in the upscale beach city as well as other communities in Los Angeles and Ventura counties.
The fire has destroyed at least 177 homes and other structures with a full count still underway, and has charred more than 83,000 acres as of late Saturday, officials said.
"Our firefighters have been facing some extreme, tough fire conditions that they said they've never seen in their lives," said Los Angeles County Fire Chief Daryl Osby.
Governor Jerry Brown asked US President Donald Trump to declare a major disaster to bolster the emergency response and help residents recover.
"We're putting everything we've got into the fight against these fires and this request ensures communities on the front lines get additional federal aid," Brown's letter said.
Trump, on a trip to France, said in a Twitter post early Sunday, "With proper Forest Management, we can stop the devastation constantly going on in California. Get Smart!"
The Republican president has previously blamed California officials for fires and threatened to withhold funding, saying the state should do more to remove rotten trees and other debris that fuel blazes.
State officials have blamed climate change and said many of the burn areas have been in federally managed lands.