More than 500,000 people have been ordered to leave their homes to escape wildfires in California in the biggest US evacuation since Hurricane Katrina.
Fierce winds are fanning fast-moving fires that have ravaged land from Santa Barbara to the Mexican border.
The fires have left three dead, burned down 1,300 homes and businesses, and are threatening 68,000 more properties.
President George W Bush will visit the state on Thursday, after declaring a state of emergency in seven counties.
A White House spokeswoman said Mr Bush, whose administration was accused of a sluggish response to Hurricane Katrina on the Gulf Coast two years ago, wanted to "witness first-hand" the crisis.
Up to 300,000 acres (120,000 hectares) of land have been scorched - an area bigger than New York City.
Forestry officials say the seasonal Santa Ana winds are hampering their efforts to contain 19 fires raging across the state, and high wind warnings will remain in effect for most of the region until Wednesday afternoon.
At least 38 people have been injured in addition to the three confirmed deaths, a spokesman for California's Office of Emergency Services (OES) told the BBC.
He said so far about 321,000 people had obeyed orders to evacuate state-wide.
In San Diego County, which has been hardest hit, firefighters have been working in difficult conditions.
"We've been faced with winds of 60 to 70mph. We've been faced with embers from that fire floating in the air a half-a-mile to three-quarters of a mile away from the fire, underneath people's roofs, onto their back yards, starting those things on fire," spokesman Maurice Luque told the BBC.
One San Diego firefighter, Mitch Mendler, said: "It was like Armageddon. It looked like the end of the world."
County officials placed evacuation calls to 346,000 homes, ordering about 560,000 people to leave - although some 50,000 were allowed to return late on Tuesday.
In Orange County, officials said the number of fires had stretched resources to breaking point.
Up to 10,000 evacuees stayed overnight at Qualcomm Stadium in San Diego, while other residents have sought shelter in schools, community centres and fairgrounds.
"I'm worried for my baby, my house, my kids, everything," Ana Ramirez, a 30-year-old pregnant woman who was taking shelter in the stadium with her four-year-old daughter, told Reuters news agency.
Ambulances and school buses were used to move hundreds of people from hospitals, nursing homes and prisons.
San Diego Mayor Jerry Sanders told people to "stay at home, stay off the freeways" so fire crews and evacuees could keep moving.
California Governor Arnold Schwarzenegger has asked the president to upgrade the fires to a "major disaster".
"This disaster is of such severity and magnitude that effective response is beyond the capability of the state and local governments," Mr Schwarzenegger said.