Two of Northern California's more than 1,400 wildfires choked parts of the Sierra Nevada foothills, darkening a 100-mile stretch between Sacramento and Reno with clouds of black smoke.
The fires in the Tahoe National Forest blanketed the Interstate 80 corridor linking the two cities and the foothill communities in between where tens of thousands of people live. The flames forced the evacuation of the tiny Gold Rush community of Washington.
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Along the Pacific, firefighters hoped coastal fog would help them gain ground against a blaze that was just 3 percent contained in the storied town of Big Sur. John Heil, a spokesman for the U.S. Forest Service, said it had blackened nearly 62 square miles, or about 39,600 acres.
Firefighters made headway against a blaze of comparable size in the Shasta-Trinity National Forest, increasing their containment to 23 percent. But the location hampered their efforts.
"It is extremely steep, very rugged territory, and there are a lot of injuries, twisting ankles, slipping on hills," said Jason Kirchner, another Forest Service spokesman. Burning debris is "rolling downhill right past your containment line. It's very complicated, difficult, dirty firefighting work."
Fire crews inched closer to getting some of the largest of 1,420 blazes surrounded, according to the state Office of Emergency Services. Some 364,600 acres — or almost 570 square miles — of forest, grass and brush had burned.
A "red flag warning" — representing the most extreme fire danger — was still in effect for extreme northeastern California, northwest Nevada and eastern Oregon, the National Weather Service said.
Lower-than-average rainfall and record levels of parched vegetation likely mean a long, fiery summer throughout northern California, according to the Forest Service's state fire outlook, released last week.
The fires were mostly started by lightning storms that were unusually intense for so early in the season. But summer storms will probably be even fiercer, according to the Forest Service.
"Our most widespread and/or critical lightning events often occur in late July or August, and we have no reason to deviate from that," the agency's report said.
The blazes have destroyed more than 50 buildings, said Gregory Renick, state emergency services spokesman.
In Arizona, strong wind turned a 500-acre wildfire away from the remote mountain community of Crown King north of Phoenix, officials said Monday. However, there was still no containment and the community was still considered threatened, said Prescott National Forest spokeswoman Debbie Maneely. About 120 residents voluntarily evacuated Sunday as flames got to within a mile of the former mining town.
Crews in central New Mexico's Manzano Mountains were doing mop-up operations Monday on an almost 9-square-mile fire that destroyed six homes and 10 outbuildings. Residents who left last week were allowed to return home Sunday. The fire, started by lightning June 23, was 85 percent contained.
In Guffey, Colo., about 40 miles west of Colorado Springs, most of the 100 residents who fled a 1,115-acre lightning-started wildfire were allowed back home Sunday. Final evacuation orders were expected to be lifted Monday morning.