By Laura Zuckerman

SALMON, Idaho (Reuters) - Authorities on Saturday ordered the evacuation of a small mountain resort in Idaho as firefighters braced for the possibility that a wildfire that has charred 82,000 acres could reach the town of Featherville in the evening.

Smoke from the Trinity Ridge Fire in the Boise National Forest blanketed roadways leading to Featherville, raising health concerns and reducing visibility, said Gary Walker, spokesman for the Elmore County Sheriff's Office.

Featherville has fewer than 100 full-time residents but vacation homes and rental cabins swell the summertime population to as many as 1,000. It was unclear how many people had remained in Featherville in recent days after warnings of a possible evacuation were issued.

The fire is one of dozens burning out of control across 10 drought-parched western states, including a blaze that destroyed dozens of homes this week in Washington state and another that threatened a town in Southern California.

The order to exit Featherville came as the fire, driven by wind gusts and low humidity, gained an additional 10,000 acres overnight, blazing just three miles west of the town.

On Saturday, crews stood guard to protect buildings in the town as firefighters on its outskirts prepared to torch the swath of land separating the community from the fire marching down the mountainside.

The burn-out operation is designed to destroy the brush, trees and other fuels that would otherwise feed the flames, fire information officer Steve Till said.

"We are ready to engage the fire when it comes off the mountain but we will engage it on our terms rather than its terms," said Till.

In Washington state, soaring temperatures and high winds along with the threat of lightning on Saturday complicated efforts to hold the line against the Taylor Bridge Fire in the northwest part of the state near the town of Cle Elum. Continued...