KIOWA, Colo. – A fast-moving wildfire forced the evacuation of about 50 homes near Denver on Wednesday as flames blackened a landscape of rolling grasslands and ponderosa pines.
Deputies went door-to-door warning residents to leave a cluster of houses about 25 miles southeast of Denver. Two air tankers were dropping fire-retardant on the blaze.
"It's doubling in size every two hours," Elbert County Sheriff Bill Frangis said. One firefighter suffered a heat-related injury, and one horse was burned, he said.
Eleven fire departments were battling the flames, which were being driven by winds of 10 to 15 mph that authorities feared could strengthen to 30 to 35 mph.
Firefighters were hampered by relentless heat. Denver reached 105 on Wednesday, tying the all-time record for hottest day, set on Aug. 8, 1878, according to the National Weather Service (search). It was the second straight day of triple-digit temperatures, far above the normal highs in the upper 80s.
Elsewhere on Wednesday, fire crews battled two blazes near Mesa Verde National Park in southwestern Colorado and braced for the possibility that lightning could spark new blazes.
Fire information officer Jen Chase said trees were so dry that the probability of lightning starting a fire was 100 percent, and any new fires were likely to spread quickly.
A nearly 200-acre lightning-caused fire on the Ute Mountain (search) Ute Indian reservation was 40-percent contained, and a second blaze on the reservation covering 2,318 acres was 75 percent contained.
Crews used tactics to avoid damaging fragile archaeological sites and artifacts, dropping retardant from the air.
Archaeological treasures on the reservation rival those at Mesa Verde National Park (search), said Tom Rice, the tribe's resource adviser. They include cliff dwellings, petroglyphs, stone tools and pottery.
In southern Arizona, a 22,500-acre fire was about 75 percent contained, thanks to burnouts and heavy rain, lessening the threat to about 30 homes and cabins and wildlife habitat in Madera Canyon.
Full containment of the blaze was expected by Thursday evening, said fire spokeswoman Donna Nemeth.
In Northern California, firefighters contained a wind-blown wildfire that grew to more than 10,000 acres early Wednesday but burned past a nuclear weapons laboratory and some 500 homes without causing major damage, said Chopper Snyder, a California Department of Forestry dispatcher.
The fire left the Lawrence Livermore National Laboratory untouched after an initial scare. Officials at the lab had declared an emergency, allowing other agencies to help protect an experimental test site at the facility.
The National Interagency Fire Center said 36 large fires were active Wednesday in Alaska, Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah and Wyoming. Nearly 3.9 million acres of land has been burned so far this year, compared with 4.4 million at this time last year.