Dozens of wildfires scorch US West

It could be days before officials will be able to assess the damage done to a small town by California's largest wildfire, one of dozens of blazes scorching lands across the US West.

Over the weekend, the massive Dixie Fire roared through the remote Northern California community of Indian Falls.

The blaze had already levelled at least 16 houses and other structures, but a new damage estimate wasn't immediately available because flames were still raging in the mountain area on Monday.

Erratic winds and the potential for dry lightning added to the challenges facing firefighters already working in steep, hard-to-reach terrain.

Gusts also hindered containment efforts and the problem could get worse with the predicted arrival of pyrocumulus clouds - literally meaning "fire clouds" - which can bring lightning and the risk of new ignitions.

Fire officials said the blaze had charred nearly 800 square kilometres of timber and brush in Plumas and Butte counties. It was 22 per cent contained on Monday and more than 10,000 homes were still under threat.

Authorities were hopeful that improving weather will help them continue to make progress against the nation's largest wildfire, the Bootleg Fire in southern Oregon.

It was 53 per cent contained after scorching 1700 square kilometres of remote land.

The lightning-caused fire has burned at least 70 homes and some 2000 residences were under evacuation orders.

In Montana, crews were trying to keep the 30-square-kilometre Devil's Creek Fire from reaching Fort Peck Reservoir along the Missouri River in Garfield County. It's one of three major fires in Montana.

Elsewhere in California, the 280-square-kilometre Tamarack Fire south of Lake Tahoe continued to burn through timber and chaparral but firefighters made progress, aided by cooler weather.

The fire was 54 per cent contained and evacuation orders that affected some 2000 residents in 15 communities on both sides of the California-Nevada state line had been lifted.

The fire, sparked by lightning on July 4 in Alpine County, California, has destroyed at least 23 buildings, including more than a dozen in Nevada.

More than 85 large wildfires were burning across the country, most of them in Western states.

They had burned over 6100 square kilometres of land.