RENO, Nev. (AP) — Triple-digit heat across much of the U.S. West hampered crews battling dozens of wildfires Thursday, including one threatening the main travel route to the Burning Man counterculture festival in the Nevada desert.
Thousands of people have been driven from their homes amid hot weather in Oregon, Montana and California, where a blaze burned 10 homes and threatened 500 more near a hard-hit community and another kept a popular road to Yosemite National Park closed.
A fire in Montana, about 60 miles south of the Canadian border, destroyed five cabins and five other structures and threatened 130 more buildings, fire officials said.
In Nevada, more than 70,000 people were expected at the Burning Man art and music celebration in the Black Rock Desert by the time it culminates Saturday night with the burning of a towering effigy, and the vast majority get there by a state highway that was closed for several hours because of the fire.
"The traffic is moving, but you had a lot of congestion built up so it's very slow going," Nevada Highway Patrol Trooper Dan Gordon said of State Route 447.
The lightning-sparked fire has burned about 45 square miles (116 square kilometers) and is about 40 miles (64 kilometers) south of the festival. There were no reports of injuries.
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"It's not close to Burning Man at this time," Interagency Fire spokesman John Gaffney said. "There's a considerable distance between the fire and the festival. At this point, the goal is to keep the road open as much as we can."
Interagency Fire spokesman John Gaffney said the heat, expected to rise to 100 degrees, was one of the biggest concerns for crews fighting the flames by the air and ground. It's chewing through brush that's 1 to 2 feet high, he said, and high temperatures were expected through the weekend.
Burning Man spokesman Jim Graham said in an email that the local festival airstrip, which is built each year, is open and the celebration was continuing as scheduled.
"At the moment there is no impact," he said.
Other fires in Nevada closed a 65-mile stretch of highway just south of the state line with California and burned a remote part of a vast former nuclear proving ground.
Nevada National Security Site spokeswoman Tracy Bower said the lightning-sparked fire covered almost 4 square miles (10 square kilometers) but wasn't considered a threat to people or buildings.
More than 1,000 nuclear detonations occurred at the former Nevada Test Site north of Las Vegas from 1951 to 1992. It now hosts non-nuclear experiments and safety training.
Elsewhere, thousands of people have fled about two dozen fires in Oregon alone, and more than 1,000 homes and businesses have evacuated near a popular vacation spot at a Montana lake as dozens of other blazes burned.
In Northern California, more than 1,000 firefighters were able to slow the growth of a nearly 5-square-mile wildfire (13-square-kilometer) overnight near the town of Oroville, an area already hard-hit by fire and a massive evacuation earlier this year caused by damage to sections of the nation's tallest dam.
It was partially contained, but about 500 homes remained in its path. Gusty winds that fueled the flames Wednesday subsided but the oppressive heat did not.
Fires also burned near Yosemite National Park, evacuating nearby towns and keeping a popular road into the park shut down. About 58 homes near the park were destroyed earlier this summer.
Air quality from wildfire smoke is a problem in Montana and Oregon, where athletic events — from kayaking and half-marathons to high school football games — have been postponed in the outdoors-loving state.
Associated Press writers Olga Rodriguez in San Francisco, Matt Volz in Helena, Montana, Steven DuBois in Portland, Oregon, and Ken Ritter in Las Vegas contributed to this report.