MOUNTAIN HOME, Idaho -- Wind-fanned wildfires in southern Idaho are proving stubborn, but across the West as a whole, firefighters are gaining ground and keeping an eye on the weather.
A fast-moving blaze spread across nearly 300 square miles of sagebrush and dry grass, authorities said Monday.
More firefighters were headed to that lightning-sparked fire, which has spread to nearly 300 square miles by Monday after it ignited Saturday. At one point, it was threatening six homes in the Castleford area, west of Twin Falls.
"The fire has been pretty well laid down near Castleford," said Heather Tiel-Nelson, a spokeswoman for Bureau of Land Management.
Interstate 84 was closed in both directions near Mountain Home Monday night as a precaution in another blaze, according to the Idaho Transportation Department. The road was closed from exit 74, Simco Road, to exit 114, seven miles west of the Glenns Ferry area.
The U.S. Bureau of Land Management estimates the Benwalk Fire at close to 12,000 acres, and reports structure protection has been put in place for homes and businesses north of the interstate.
A steady 20-mph wind has been pushing the blaze northwest, where crews were focusing their efforts, said BLM officials. Strong gusts also spread flames of a separate fire to the Saylor Creek bombing range, a training space operated by the Mountain Home Air Force Base, but no structures were threatened.
"The wind has been a big factor," said another BLM spokeswoman, Kyli Gough. "With these light fuels being the way they are, even a small amount of wind can pick up the fire and move it pretty quickly."
Elsewhere across the West, firefighters made progress in Utah, Wyoming, Colorado and Montana, the site of the country's biggest active wildfire, according to the National Interagency Fire Center. But forecasts for the rest of the week called for heat, lightning and wind across much of that area, which could fuel more blazes.
A wildfire that has burned more than 390 squares miles in southeastern Montana was 90 percent contained. A separate fire in the same region of the state, near Fort Howes, was 65 percent contained after blackening nearly 97 square miles.
Winds were also problematic at a California blaze near the farming community of Maxwell in Colusa County. The fire started Sunday and consumed about 1,600 acres. Several miles to the west, a wildfire burned more than 15 square miles in the Mendocino National Forest, closing campgrounds and prompting the residents of a handful of homes to flee early Monday.
Other fires in the West include:
-- Wyoming's largest fire, burning about 150 square miles northwest of Wheatland, was 75 percent contained.
-- In Utah, cooler temperatures and rain helped firefighters with the state's largest wildfire. The 108,000-acre blaze in Millard and Juab counties was 91 percent contained, officials said.
-- In Washington state, a wildfire caused by humans has burned 675 acres between Entiat and Chelan.
-- Oregon authorities braced for an outbreak of wildfires after the National Weather Service said conditions in central and eastern parts of the state were ripe for fires. A blaze in Grant County, east of the John Day Fossil Beds National Monument, burned 290 acres, and winds were pushing a 2,800-acre wildfire west of Frenchglen. A 70-square-mile grass fire in southeast Oregon forced employees at a state transportation station to evacuate and also shut down traffic on U.S. Highway 95 at one point.
-- In Colorado, Gov. John Hickenlooper lifted a statewide fire ban he ordered last month after recent rain, but some local officials, including ones in Garfield County, say they're keeping the ban in place. The rain washed out a main highway to Leadville and caused a mudslide in northern Colorado, creating problems in fire-ravaged areas now susceptible to mudslides.