By Laura Zuckerman
SALMON Idaho, Aug 19 (Reuters) - A wildfire roared out of control for a ninth day on Sunday through rugged, tinder-try terrain in Idaho's Boise National Forest, where firefighters kept up a battle to prevent flames from reaching a newly evacuated town east of the state capital.
The so-called Trinity Ridge blaze has swallowed well over 88,000 acres (35,600 hectares) of sagebrush and timber in south-central Idaho since it was ignited on Aug. 3 by an off-road vehicle that caught fire, authorities said.
The fire was one of several blazing largely unchecked across Idaho on Sunday, and one of nearly three dozen that have devoured more than 1 million acres throughout nine drought-stricken Western states, according to the National Interagency Fire Center in Boise.
Except for a U.S. Forest Service firefighter killed by a falling tree last Sunday in northern Idaho, no major injuries or loss of life have been reported during the past week.
Red-flag warnings for high fire hazards were posted through much of Idaho on Sunday as forecasts called for possible thunderstorms that could bring lightning and gusty winds. Sc a ttered thunderstorms also were predicted in northern California, Oregon, Washington and elsewhere in the West.
The Trinity Ridge Fire continued to pose one of the greatest imminent threats to property in the region.
As of Sunday, a force of more than 1,000 firefighters had managed to carve containment lines around just 5 percent of the fire's perimeter while keeping the blaze from overrunning the former mining town of Featherville on the banks of the South Fork Boise River.
The tiny village, located about 50 miles (80 km) east of Boise, is home to fewer than 100 year-round residents, but vacation homes and rental cabins swell its summertime population to as many as 1,000.
The town was evacuated on Saturday due to thick smoke and reduced visibility from the fire, and the only road leading to Featherville was closed to all but emergency traffic. It was not clear how many people were still in the area when it was ordered cleared, but fire information officer Mallory Eils said nearly 30 people were known to be staying put in town.
At least one leading edge of the sprawling fire was reported to have crept to within 3 miles (5 km) of town.
Although smoke from the fire has created unhealthy air that is especially hazardous to children, the elderly and people with respiratory ailments, it has paradoxically helped slow the fire's advance at times by blocking out the sun, cooling temperatures on the ground.
On Sunday, crews stood by to protect buildings in town as firefighters prepared to deliberately torch swaths of land on its outskirts to remove brush, trees and other vegetation that could otherwise act as fuel for advancing flames, authorities said. (Writing and additional reporting by Steve Gorman; Editing by xxxxx)