The Knowles Fire near Paradise in Sanders County expanded to more than 1,800 acres by Thursday morning.  

The wildfire is burning in steep, rocky terrain in the Knowles Creek drainage and the ridges above Knowles Creek, officials said in an Aug. 21 update. Crews were working to build direct and secondary indirect firelines to prevent it from reaching homes and timberland as well as block it from spreading along the Montana 200 corridor. 

The blaze, which began Aug. 17, was listed as 0% contained as of Thursday afternoon. The Sanders County Sheriff's Office has issued a pre-evacuation notice to McLaughlin area residents.  

More than 200 people are working the fire, including two hotshot crews and five hand crews. Four engines are on scene, joined by multiple pieces of heavy equipment, officials said.   

Officials said that the fire featured short crown runs and short-range spotting on Wednesday.  

Fire crews received aid by air earlier in the week, including from helicopters and air tankers, which officials credited with helping to slow the blaze's spread and reduce its intensity. But given the increased fire activity regionally, it was unclear if ground crews could count on similar aerial support on Thursday. Winds were expected to be light to moderate and blowing out of the west, southwest and northwest before shifting to the east and northeast in the evening.  

Authorities expected the fire behavior would remain active.  

The Full Curl Wildlife Management area, a 440-acre stretch of land on the north side of the Flathead River accessible only by boat, remains closed. For a list of closed Forest Service roads in the area, go to: fs.usda.gov/r01/lolo/alerts/knowles-fire-closure. 

News Editor Derrick Perkins can be reached at 758-4430 or [email protected].