Two homes have been evacuated in proximity to the Glacier Rim Fire that has covered roughly 80 acres in the North Fork.

Fire officials say six structures are threatened by the fire, but a general evacuation has not been ordered.

A coalition of 90 firefighters worked on Monday to dig lines around the fire, which had jumped across the North Fork of the Flathead River into Glacier National Park in spots.

Flathead County Sheriff Chuck Curry said crews have made progress on fire lines to the east, north and south of the fire. Monday’s work focused on containment of the west side.

Heavy equipment, including bulldozers, has been used to clear the area. Two contracted helicopters are also dropping water from above.

Firefighters were challenged by heavy, dead timber. There is a danger of falling trees since the fire is burning in the area of the 2003 Robert Fire.

Hot weather and very dry conditions have contributed to the fire’s spread. As of Monday afternoon, officials say it was 25 percent contained.

Fire crews are made up of personnel from the U.S. Forest Service, Glacier National Park and Montana Department of Natural Resources and Conservation. The Flathead County Office of Emergency Services is assisting and county search and rescue members were ferrying firefighters across the river.

Fire trucks from other Flathead Valley departments including Evergreen, Columbia Falls and Blankenship have assisted the firefighting effort.

After being closed shortly on Saturday, the North Fork Road remains open to the public. The same goes for the river.

“The request for drivers and floaters is that they don’t stop in the fire area,” fire information officer Colter Pence said.

The fire started on Saturday afternoon. Officials believe it is human-caused, but a specific origin is still not known.

The National Weather Service called for continued high temperatures and possible thunderstorms before midnight Monday. The weather pattern could also bring sharp wind gusts, which worries officials.

“The big concern is weather,” Curry said. “If the wind picks up, that’s bad.”

Reporter Matt Hudson may be reached at 758-4459 or by email at mhudson@dailyinterlake.com.