FLAGSTAFF, Ariz. (AP) -- Firefighters are bracing for the return of ferocious winds in the Southwest after a brief reprieve allowed them to attack flames from the air for the first time in days as a half-dozen large wildfires continue to grow in Arizona and New Mexico.
More than 500 firefighters were manning fire lines in the two states and more help was on the way Friday when the largest type of management team is scheduled to take command of resources at one of the biggest, most dangerous fires near Flagstaff, Arizona.
Spirits were lifted Thursday as helicopters were able to start dropping water on that blaze for the first time. It has burned more than 32-square miles (83-square kilometer), forced evacuations of 765 homes and destroyed at least two dozen structures since it broke out on Sunday.
Aerial attacks also resumed in northern New Mexico, where at least one airtanker was able to join the effort northeast of Santa Fe -- something that's likely to be impossible on Friday.
Sheriff's deputies called for additional evacuations Thursday of scattered homes and closed some roads at a big fire burning in a rural area southeast of Taos, New Mexico, where no structure damage has been reported.
But fire officials and weather forecasters across the region warn the worst may be yet to come.
"There is high confidence that a widespread extreme and catastrophic fire weather event will occur on Friday," Santa Fe National Forest officials said late Thursday.
"We are urging the public to stay vigilant, to continue to watch for expected changes in evacuation status and be prepared to leave in a rapid manner," officials said.
Sustained winds of 30-50 mph (48-80 kph) are forecast there Friday morning, with gusts from 60-80 mph (97-129 kph) in the afternoon from the Gila Mountains up through the Rio Grande Valley to neighboring highlands.
The combination of the high winds, warmer temperatures and extremely dry conditions will make for an atmosphere that's "pretty much on steroids," said Scott Overpeck with the National Weather Service in Albuquerque.
"This is not typical," he said, looking ahead to what he said could be potentially explosive fire growth on Friday. "This is really one of those days we need to be on our toes and we need to be ready."
Arizona Gov. Doug Ducey on Thursday declared a state of emergency in Flagstaff's Coconino County. The declaration clears the way for state funding for evacuations, shelter, repairs and other expenses. However, the money can't be used to reimburse home and business owners for losses.
About 30 structures have been destroyed, but it's still unclear how many were homes, the county sheriff's office said.
On Thursday, firefighters fanned out across blackened landscape in Arizona's high country, digging into the ground to put out smoldering tree stumps and roots as helicopters buzzed overhead with buckets of water to drop on a massive blaze.
Wildfire has become a year-round threat in the West given changing conditions that include earlier snowmelt and rain coming later in the fall, scientist have said. The problems are exacerbated by decades of fire suppression and poor forest management along with a more than 20-year megadrought that studies link to human-caused climate change.
At a fire that's consumed about 3 square miles (8 square kilometers) of timber and brush and forced evacuations near Prescott, Arizona, Forest Service officials reported the blaze continues to burn "in continuous thick, dry, dead and down fuels in very rugged terrain."
"Erratic winds and fire behavior is making conditions hazardous for firefighters," who are "being directed to not put themselves in situations where the risks are high and probability of success is low," Prescott National Forest officials said in an update Thursday.
Popular lakes and national monuments closed in Arizona -- including Sunset Crater Volcano National Monument outside Flagstaff because the wildfire moved directly over it, blackening trees, and burning tools and vehicles in a maintenance yard, said monument spokesman Richard Ullmann.
The Coconino National Forest has closed where the wildfire is burning but has not enacted broader fire restrictions or closures. A sign at a gate warns of potential loose debris, falling trees and branches, and flash floods.
Fire restrictions go into effect Friday at National Park Service sites in New Mexico, including Valles Caldera National Preserve and Bandelier National Monument.
In Colorado, firefighters got a handle on two small wildfires in the southern and northern part of the state on Thursday while contending with strong winds.
The Boulder County blaze was sparked by the battery of a crashed drone that researchers were using to study severe weather, the sheriff's office said Thursday. Researchers used a fire extinguisher, but the fire spread quickly in high winds, authorities said. The other fire damaged or destroyed an estimated 15 structures, including homes, in Monte Vista, a community of about 4,150 people surrounded by farm fields, police said.