New evacuations were ordered overnight in Arizona as firefighters attempted to gain ground on the Wallow fire, which has burned 193,000 acres near the New Mexico-Arizona state line.
More than 2,200 people fled their homes as the fires advanced, fed by hot winds and dry fuel. There is concern that the blazes could expand today, fed by hot gusty winds as well as lightning storms that can trigger new fires.
"It was horrific; the likes of a fire I've never seen from the air before," Arizona Gov. Jan Brewer said.
Residents have turned to using inhalers in attempts to breathe through the thick smoke.
The blaze, which began May 29, became the third-largest in state history, officials said Sunday. Emergency crews intentionally started a series of smaller fires Saturday, trying to halt the advance of the fire.
The Wallow fire has devastated an estimated 301 square miles, toward mountain communities in eastern Arizona.
Because of high-wind threat, residents in the summer resort town of Greer and other communities on the eastern edge of the White Mountains were placed under an evacuation alert.
The town emptied out Saturday in what was supposed to be one of the busiest weekends of the year for vacationers.
"It's scary. I see black smoke and I panic, you know," said Shaneen Elefante, who works at a local lodge. "It's very devastating to a lot of the families -- the people who work up here, just the whole community."
Firefighters have worked around the clock to protect Arizona communities from the massive wildfire, which has already cost $3 million to fight.
Helicopters dumped water and retardant on smaller fires burning in far southern Arizona to avoid fire threatening two communities and a church camp. As of late Saturday, crews were able to control the blaze in that area.
Temperatures are set to reach the high 90s across Arizona on Monday.
The state saw its worst fire in 2002, when the Rodeo-Chediski fire burned 469,000 acres across the central section of the state along the southwestern edge of the Colorado Plateau. In 2004, the Cave Creek complex fire burned 248,000 acres in 2005.
Even if the backfires halt the progress of the blaze, it will be days before residents will be allowed to return to assess the damage to their homes and farmlands.