ROUTT COUNTY, Colo. — More firefighters and equipment have been ordered to help fight the Middle Fork Fire burning north of Steamboat Springs.
As of this writing, 90 firefighters are battling the fire.
The lightning-caused fire is burning in the Mount Zirkel Wilderness about 10 miles north of Steamboat Springs.
Fire activity increased Thursday and was forecasted to do much of the same Friday.
Fire managers said dry conditions, warm temperatures and low humidity are helping feed the fire
As of Thursday, the fire had burned 11,992 acres. Friday's update said the fire had torched 16,120 acres.
No evacuations have been ordered, but there are wilderness and trail closures.
The Middle Fork Fire was first reported on Sept. 6.
It is burning about 100 driving miles west of the Cameron Peak Fire, which is in Larimer County.
The Mullen Fire, which started in Wyoming and entered Colorado, is burning north-northeast of the Middle Fork Fire.
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