The Marston Fire north of Whitefish made a run over the weekend and now is estimated at 6,700 acres.

The lightning-caused fire on the Kootenai National Forest is just 15 percent contained after it grew on its northeast flank.

The blaze hasn’t yet moved onto the Flathead National Forest, and is about 20 miles away from Polebridge. Cool weather and some showers on Sunday helped slow the growth.

Officials expect the fire will continue backing downhill toward Deep Creek and Sink Creek if cool conditions persist.

Fire spokesman Tom Rhode said firefighters were drawing a line in the dirt while they could.

“It wasn’t very active yesterday,” he said Monday. “The west side has line on it, that’s the 15 percent containment, about nine miles. Crews are now working around the south and north sides of the fire. It comes creeping down to our lines, but we stop it. It hasn’t moved.”

A Montana National Guard Chinook helicopter and a medium helicopter are assisting with water drops on hot spots.

The Marston Fire is a part of three fires burning within the Northeast Kootenai Complex. The Sunday Fire is 60 acres and is now 100 percent contained. The Barnaby Fire burning in rugged terrain is 50 acres and is being monitored by helicopters.

A fire camp is set up on Ant Flat Road for the 285 personnel who continue to work the complex.

The complex received a tenth of an inch of precipitation over the weekend.