The Peakaboo Fire which is burning in a remote, rugged area about 50 miles west of Craig has grown to 8,000 acres.
It nearly doubled in size since Wednesday with extreme fire behavior that included torching of trees and significant uphill runs along Peakaboo Ridge. It's 5 percent contained.
Three ranches, multiple ranch structures and Browns Park National Wildlife Refuge are located a couple miles south of the fire and are being monitored and patrolled, but no structures are threatened.
Lightning sparked the fire on June 27.