SISTERS, Ore. — Evacuation orders affecting hundreds of people were issued in California and Oregon as wildfires neared small towns, including one that’s a prime location for viewing the eclipse.

About 600 residents were told to leave the tourist town of Sisters, Oregon, and authorities said Saturday another 1,000 people had been told to be ready to leave if necessary.

Sisters is located on the edge of a 70-mile swath of the state where the moon will completely blot out the sun.

Crews were expecting a tough day Saturday with winds gusting to more than 20 mph.

On Monday, they will have to contend with the solar eclipse that fire officials say will ground all firefighting helicopters and most fixed-wing aircraft for about 35 minutes as the moon’s shadow passes over the area.

In California, authorities issued an evacuation order for the small town of Wawona as a week-old fire in Yosemite National Park grew and air quality reached a hazardous level.

The U.S. Forest Service said the fire grew to more than 4 square miles overnight because of winds from thunderstorms. Authorities ordered people to leave as air quality was expected to worsen.

Wawona, with a population of 1,000 to 2,000 people at any given time, is less than 2 miles from the fire. The evacuation order included the historic Big Trees Lodge, formerly known as the Wawona Hotel.

The fire has closed campgrounds and trails in the national park since it began a week ago. It was 10 percent contained.

In Montana, 155 National Guard troops arrived to monitor about three dozen security checkpoints in an area south of Missoula that was evacuated because of a fire that flared up after burning since at least July 15. The fire destroyed two homes and several outbuildings Thursday.

The Missoulian reported that heavy smoke has settled into valleys and officials warned of poor air quality.

Idaho’s two largest wildfires were burning mostly in wilderness areas.

One fire burned 17 square miles in Frank Church River of No Return Wilderness, and another in Gospel Hump Wilderness had burned 21 square miles.