Hundreds of people were ordered to evacuate their homes after a raging wildfire that has already charred almost 100,000 acres began to nip at the edges of two Idaho mountain resort towns.
The lightning-sparked blaze dubbed the Elk Fire has already gobbled up around a dozen homes in the towns of Pine and Featherville, and authorities have intensified calls for more people to leave.
The fire that started last Thursday is a "top priority," according to the National Interagency Fire Center.
"This is a more serious situation. We might be hopeful about protecting Pine and Featherville again, but it's a different beast," fire spokesman David Eaker told Reuters.
It is the second time in two years that the towns, about 70 miles east of Boise, have been ordered emptied over fires burning in the Boise National Forest.
Officials said some residents may be staying because of a false sense of security fostered by the successful defense of the towns last year.
The count was hampered because many of the homes are owned by summer residents who do not live there year round.
The fire has already ravaged another small mountain town. Officials say 53 structures in the Fall Creek area have been destroyed.
Hundreds of firefighters have been assigned to tackle the blaze -- whose threats are compounded by steep, rugged terrain, low humidity, gusting winds and thick smoke, authorities said.
But they will not be aided by the weather, according to Kevin Roth, lead meteorologist at weather.com.
"Overall the weather is not going to be very helpful," he said. "It's going to be very warm and quite dry, so the humidity is going to be very low. These two conditions help the fire to spread. Also there is no threat of rain over the next seven to 10 days."
"They are going to have temperatures well into the 90's, so dry and hot."
The Elk Fire is only one of three big blazes in the state. The Pony Fire Complex near Mountain Home has swallowed 144,000 acres; the Beaver Creek Fire has burned some 38,000 acres near Ketchum.
The destruction prompted Gov. C.L. “Butch” Otter to declare Idaho a disaster area. The order allows state agencies to send more resources to help suppress the flames.
In Utah, a lightning-sparked wildfire has destroyed 13 homes and threatened hundreds of others near Park City.
Shifting winds pushed the fire toward homes in the Lake Rockport Estates subdivision about 10 miles outside Park City. It destroyed a dozen homes on Tuesday, plus another home overnight. Fire officials say it also burned 20 outbuildings and several vehicles and boats.
The West has already suffered a series of destructive wildfires in 2013. Colorado experienced the most destructive wildfire in its history in June, which killed two and destroyed about 500 structures. As that fire burned, 11 other fires plagued the state and more threatened other parts of the Southwest.
Reuters and The Associated Press contributed to this report.