Air and ground crews resumed work against a 500-acre fire in the Rocky Mountain foothills about 30 miles southwest of Denver that impacted more than 100 people. The Lime Gulch Fire, possibly triggered by lightning, threatened no structures in Pike National Forest.
In southern Colorado, a 300-acre fire in Huerfano County forced at least 175 people to stay at a Red Cross shelter at a high school.
In Arizona, firefighters braced for more hot, windy weather Thursday as they battled a wildfire in Prescott National Forest that scorched nearly 12 square miles. The blaze erupted Tuesday afternoon and led to the evacuation of 460 homes.
To the north, smoke from another fire that broke out Wednesday was visible from Grand Canyon National Park. No structures were immediately threatened.
A blaze in southern New Mexico's Gila National Forest grew to 47 square miles.
In Northern California, hundreds of residents returned home as crews aided by lower temperatures and higher humidity extended their lines around a wildfire near a main route into Yosemite National Park. Only about 50 homes on two mountain roads remained under evacuation orders, the California Department of Forestry and Fire Protection said. The fire, sparked Sunday by a campfire that wasn't fully put out, led to the evacuation of about 800 homes at its peak.
In Southern California, a nearly 6-square-mile fire in the San Bernardino National Forest was 83 percent contained.
The fire near Denver was burning in steep, heavily forested mountain terrain, south of where last year's Lower North Fork Fire damaged and destroyed 23 homes and killed three people. That fire was triggered by a prescribed burn that escaped containment lines.
Some residents said they were ready to leave in minutes, having practiced fire evacuations after the Lower North Fork Fire.
Karalyn Pytel was at home vacuuming when her husband called, saying he had received an alert on his cellphone telling the family to leave. She quickly grabbed her 6-year-old daughter's favorite blanket, a laptop computer, a jewelry box and some family heirlooms before fleeing.
"I grabbed a laundry basket and just threw stuff in it. I don't even know what clothes they are," Pytel said as she arrived at an evacuation center.
Firefighters were aided by two U.S. Air Force Reserve C-130s.
The planes also were used at a 22-square-mile wildfire near Colorado Springs that has destroyed 509 homes and killed two people since it started June 11.
In northwest Colorado, an 850-acre wildfire in Rio Blanco County forced Encana Corp. to shut down oil and gas facilities, the Bureau of Land Management said. Firefighters protecting buildings at an Encana station spotted embers up to a half-mile away from the blaze.