Updated

A handful of new wildfires, some started by lightning, grew dramatically Tuesday in central Washington, and several threatened homes even as firefighters made progress against a destructive Oregon blaze.

A brush fire that jumped containment lines Tuesday night temporarily closed a 20-mile stretch of Interstate 90 in the central part of the state, said Washington State Transportation Department officials. The highway reopened late Tuesday night.

State firefighting assistance has been ordered for the Stokes Road fire, burning in north-central Washington's Methow Valley. That lightning-caused fire has grown to 600 acres. Residents of seven homes were told to leave, fire spokesman Jacob McCann said.

Another fire 10 miles north of Leavenworth quickly raced across 200 to 500 acres in heavy timber, sending up a 20,000-foot column of smoke and spitting embers as far as a mile ahead of the main blaze, fire spokesman Daniel O'Connor said. Homes were threatened there too.

That fire, too, was caused by lightning, O'Connor said.

Washington's largest wildfire, the Mills Canyon blaze near the central Washington town of Entiat, was 40 percent contained Tuesday and holding steady about 35 square miles.

Kittitas Valley firefighters worked to protect farm homes in the Badger Pocket area near Ellensburg from a wildfire burning on the northern edges of the Army's rugged Yakima Training Center.

Winds forecast as high as 30 mph Wednesday could test the Washington firefighters on all fronts.

In southern Oregon, crews trying to save rural dwellings got help from a natural force they usually dread when winds turned around a spreading wildfire.

That kept the fire from breaking out of a 4-square-mile area near the ranching town of Sprague River where crews were trying to dig containment lines, fire spokeswoman Erica Hupp said Tuesday.

The fire claimed six houses when it broke out Sunday in the Moccasin Hill subdivision, and destroyed 14 other structures, such as barns and garages.

Hupp said it began expanding Monday afternoon, making a run that covered about half the length of a football field. It was in an area where bulldozers hadn't dug lines.

The flames were moving away from Moccasin Hill, Hupp said, but if the winds hadn't forced the fire back on itself, other homes in the area would have been threatened.

"It really did kind of help the firefighters," she said.

The fire, which has burned across nearly 4 square miles, or 2,500 acres, was 15 percent contained Tuesday. Hupp said many residents who had been evacuated were back at home.

Hupp said the cause hasn't been determined, but lightning has been ruled out. Elsewhere in Oregon, weekend lightning has been blamed for dozens of fires.

A stubborn wildfire in Northern California that authorities say was sparked by exhaust from a truck threatened dozens of additional homes on Tuesday.

The Bully Fire around the rural community of Igo in Shasta County was threatening more than 68 structures, said California Department of Forestry and Fire Protection spokeswoman Teresa Rea. Some of those homes were under mandatory evacuation orders, though she didn't know exactly how many.

The fire, which began Friday and has destroyed eight homes and 10 other structures, had burned through nearly 13 square miles, or 8,100 acres, of forest land. It was 20 percent contained.

A 27-year-old Sacramento man has been charged with recklessly causing the fire and with marijuana cultivation, both felonies. Authorities said he was delivering supplies to an illegal plot when the fire broke out.

In Idaho, residents of about 60 homes in a small central Idaho town remained under voluntary evacuation Tuesday as crews fought nearly 20 lightning-caused fires in the Boise National Forest.