Red flag warnings were posted for wide areas of the Northwest on Wednesday, indicating extreme fire danger as crews battled spreading wildfires.

A group of wind-driven fires near Dayton in southeast Washington had raced across more than 15,000 acres, or more than 23 square miles, of grass, brush, trees and wheat fields.

Some 35 residents of a nursing home were evacuated Tuesday because of heavy smoke, and as many as 300 other people were urged to leave their homes. The fires near town were sparked by lightning on Monday and fanned by wind gusting to 30 mph.

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No homes had burned as of late Tuesday but some outbuildings and a couple of vehicles were lost, said Ray Steiger, a spokesman for the management team on the fire. No injuries were reported and the main fires were burning away from this town of about 2,700 people.

Meteorologists predicted scattered thunderstorms, wind and low humidity in the area Wednesday.

Red flag warnings or fire weather watches also were posted for parts of eastern Oregon, Idaho, Montana, Nevada and Utah, the National Fire Information Center said.

An evacuation order was issued Wednesday for 25 to 30 homes in a subdivision east of Billings, Mont., as a nearby wildfire grew to at least 3,300 acres, said Mary Apple, fire information officer with the Billings Dispatch Center. The blaze destroyed two homes, a barn and several outbuildings Tuesday.

About 190 homes in the Emerald Hills subdivision were ordered evacuated Tuesday but "not everyone evacuated," Apple said. The fire, fueled by timber and grass, was reported Tuesday morning; the cause was not yet known.

Oregon's largest wildfire had covered 20,000 acres, or 31 square miles, since it was started by lightning on Monday in the state's remote southeast corner.

Crews were bulldozing a line to protect the town of Fields, Ore., population 20. The fire was about 6 miles east of town Wednesday morning.

South of Burns, Ore., two campgrounds on Steens Mountain were evacuated Tuesday and campers in a third were advised to leave, all precautionary measures, said Tara Wilson, spokeswoman for the firefighters. She said the fires were miles from the campgrounds but could block evacuation routes later.

The National Fire Information Center said wildfires were reported Tuesday in Arizona, California, Idaho, Montana, Nevada, Oklahoma, Oregon, Texas, Utah, Washington and Wyoming. Fires also broke out during the night in the northwest corner of Nebraska.

So far this year, wildfires have blackened 6.8 million acres, or 10,600 square miles, compared to 6.7 million acres at this same time last year, the center said.

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