High temperatures, low humidity and wind over the weekend helped boost fire activity and grow the Pioneer Fire to more than 38,000 acres, according to the U.S. Forest Service.
More than 1,200 personnel are battling the blaze with six helicopters, 48 engines, eight bulldozers and five masticators. The fire is still 30 percent contained.
The fire was most active on its eastern side, pushing into the area between Banner and Willow creeks and southeast into the Big Owl Creek area, the agency said. Along the northern edge, which was less active, firefighters worked on contingency fire lines, anticipating growth toward Lowman.
Crews will work to improve containment lines Monday and take on burnout operations near the Sloper Mine and along Burns Ridge. Firefighters will also try to wrangle the flames around Rock Creek.
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Temperatures are predicted to be high Monday and humidity low, meaning the fire is expected to be active again.
Smoke should be visible from great distances, according to the release.
Officials urged residents to not fly drones in the area. You can get fined for flying drones in a fire area and it halts firefighting operations.
Two structures, mining shacks, were destroyed earlier in July by the fire. Ten structures, yurts on the Whoop-Um-Up campground, are still threatened by the fire, according to the release.