Stiff winds whipped up a gigantic blaze in the mountains of eastern Arizona, United States, forcing the evacuation of a third resort town and casting a smoky haze over states as far away as Iowa.

Winds of about 50 kph, with gusts above 100 kph, blew heavy smoke from the fire in the picturesque town of Greer, where most of the 200 full-time residents had already fled. Everyone still there and in nearby area known as Sunrise were ordered to leave on Monday afternoon.

"It's heartbreaking," Allan Johnson, owner of the 101-year-old Molly Butler Lodge in Greer, the oldest in the state, said of the fire barreling down on the resort town. He was pessimistic about the chances of saving the lodge and the hundreds of vacation homes in the area.

"We're numb - our entire family and our friends are just numb," he said.

Late on Monday, a huge pall of black smoke loomed over the twin towns of Eager and Springerville, home to about 7,000 people, and sheriff's officials told residents there to prepare to leave.

The winds and expected lightning are making matters worse in an area dotted with cabins and campgrounds that have long provided a cool summer getaway from the oppressive heat of the nearby desert.

The fire was estimated at about 932 square kilometers, officials said on Monday night. Officials believe an abandoned campfire may have sparked the blaze more than a week ago.

Several hundred people turned out for a community meeting on Monday night at which fire officials urged residents to be ready to evacuate if the fire continues to grow. They vowed to give residents of Eager and Springerville as much notice as possible of an evacuation.

So far, the flames have destroyed five buildings and scorched nearly 93,000 hectares of ponderosa pine forest. No serious injuries have been reported. The blaze nearly doubled in size between Saturday and Monday.

About 2,700 to 3,000 people are believed to have fled Alpine and Nutrioso late last week and headed to larger towns for shelter, Governor Jan Brewer said.

Roughly 2,500 firefighters, including many from several western states and as far away as New York, are working to contain the wildfires, Fire Information Officer Peter Frenzen said.

Arizona Governor Jan Brewer signed an emergency declaration on Monday that will allow the use of $200,000 in emergency funds and authorizes the mobilization of the National Guard if it becomes necessary.

A ridge of high pressure was carrying the haze to central Iowa, said Kyle Fredin, a National Weather Service meteorologist in Denver. The smoke was visible in New Mexico, Colorado, Nebraska and Kansas.

Fredin said the smoke wouldn't be noticeable in the Midwest, where humidity already makes conditions hazy. He said it could, however, produce striking orange-pink sunrises and sunsets.