By Keith Coffman and Alex Dobuzinskis
DENVER/LOS ANGELES (Reuters) - The number of homes destroyed by a Colorado wildfire rose above 500 on Tuesday as rain dampened the flames and allowed damage assessment teams to enter charred neighborhoods, and other threatening blazes grew in Alaska and elsewhere in the West.
Authorities said the so-called Black Forest Fire, which has burned in the rolling hills outside Colorado Springs for the past week and killed at least two people, was 85 percent contained by Tuesday.
The most destructive fire in Colorado's history has charred 22 square miles (57 square km), destroyed 502 homes, and underscored concerns that prolonged drought conditions in the U.S. West could intensify this year's fire season.
Fire incident commander Rich Harvey of the U.S. Forest Service told reporters rain had allowed crews to carve containment lines around all but one section of the blaze.
"It is anticipated we will identify additional homes considered to be a total loss," El Paso County Sheriff Terry Maketa said.
Investigators have pinpointed the area where they believe the fire started, but have not determined a cause, Maketa said, adding a U.S. Forest Service fire expert had arrived to take a fresh look at the site.
Some 2,600 people remain under evacuation orders, down from last week's peak of about 38,000.
As crews gained the upper hand over the Colorado blaze, other wildfires in California, Alaska and Arizona grew amid hot, dry conditions.
In California, a wind-whipped fire believed to have spread from an unattended campfire in tinder-dry conditions on Sunday, threatened about 800 houses and vacation cabins near Yosemite National Park on Tuesday, prompting evacuations, according to the California Department of Forestry and Fire Protection (Cal Fire).
There was no immediate word on precisely how many people had been evacuated because of the 1,600-acre (650-hectare) Carstens Fire in Northern California, which erupted near a state route leading to Yosemite National Park, Cal Fire said on its website.
"The biggest thing for us that has been challenging is conditions are so dry, and you add to the dry conditions the strong winds and that has allowed this fire to burn very quickly," Cal Fire spokesman Daniel Berlant said of the blaze, which was just 15 percent contained on Tuesday afternoon.
In Alaska, record-high temperatures above 90 degrees Fahrenheit (32 Celsius) in some areas contributed to the fast spreading of a spate of wildfires to 156 square miles (404 sq km) overnight, up from 94 square miles (243 sq km) on Monday.
Of particular concern was a blaze, caused by people near Chena Hot Springs resort in the Fairbanks area late on Monday, which had spread to 120 acres by Tuesday.
No structures have been lost, but officials imposed a temporary flight restriction on the area to reduce interference with firefighting aircraft, said Maggie Rogers, a spokeswoman for the Alaska Division of Forestry.
In Arizona, a fast-growing wildfire burning through chaparral, pine and juniper forest about 100 miles north of Phoenix forced the evacuation of at least 25 homes, officials said.
The Doce Fire has burnt up to 2,000 acres in the Granite Basin area, a few miles from the city of Prescott, said Noel Fletcher, a spokeswoman for the Prescott National Forest.
"Right now we are trying to get people out of the homes in the path of the fire," Fletcher said.
(Additional reporting by Yereth Rosen in Alaska and Tim Gaynor in Arizona; Writing by Alex Dobuzinskis; Editing by Mohammad Zargham)