Hundreds of firefighters had so far succeeded in protecting buildings, including the farm complex where the anti-government Montana Freemen holed up in a 1996 confrontation with federal agents.
However, about 50 people had been evacuated as the fire blackened stands of ponderosa pine and charred pastures and hayfields.
``We expect more wind today,'' said information officer Pat McKelvey at the main fire camp outside Jordan.
The fires made little progress Monday, when the high was only in the 80s, but temperatures were headed into the 90s Tuesday, McKelvey said.
``Dehydration is becoming our biggest health concern,'' he said. One firefighter was brought off the fire lines during the night because of dehydration.
The fires were south of the Missouri River on or near the Charles M. Russell National Wildlife Refuge.
Brenda Pluhar, whose father's ranch sits in the path of the fire, looked out the kitchen window Monday and saw billowing smoke just a mile away. To the north, south and east, she saw nothing but burned landscape.
``Beyond a quarter of a mile, there's scorched land, scorched hayfields and scorched trees,'' she said. ``It's just devastating watching the scenery go up in smoke.''
Calmer weather on Monday had helped fire crews in northwestern Montana, where about 100 homes were evacuated in the path of a 4,600-acre fire just outside Glacier National Park.
Elsewhere in the West, officials in California's San Luis Obispo County discovered that three houses and several outbuildings had been destroyed by a blaze that forced some 250 people to flee an area of rolling, oak-studded hills.
The blaze was 80 percent contained Tuesday after charring 1,200 acres near the community of Santa Margarita, California Department of Forestry dispatcher Corrin Clark said.
In Wyoming, firefighters worked Tuesday to protect six homes about a mile from a 1,300-acre blaze in Johnson County and three ranches about a half-mile from the flames. The fire had nearly doubled in size overnight to 1,300 acres and was only 10 percent contained, fire information officer Lesley Collins said.
Large fires also were active Tuesday in Arizona, Colorado, Idaho, New Mexico, Nevada, Oklahoma, Oregon, South Dakota, Utah and Washington, the National Interagency Fire Center said.
