Eight structures have been destroyed and as many as 150 are threatened by a raging wildfire that continues to expand its reach west of Flathead Lake.

The human-caused Elmo 2 Fire grew another 2,000 acres, bringing the total acres burned to 18,427 as of Wednesday morning. It was estimated to be 16% contained.

Gusting winds from the west, combined with low humidity, have quickly pushed the fire north through thick timber. According to fire information officer Sara Rouse, it’s probable that the fire will reach Lake Mary Ronan and the Big Meadow area by Thursday morning.

“It’s very active on the north end,” she said.

Four primary residences and four outbuildings had burned in the fire as of Wednesday afternoon. As many as 150 structures are threatened.

Firefighters were pulled from the north flank as conditions worsened Wednesday. And while air resources were still in use, they were unable to attack the north edge due to low visibility, Rouse said.

In response, the Lake County Sheriff’s Office expanded an evacuation order to include all residents north and south of Lake Mary Ronan Road, and all residents along the lake itself.

Rouse said the order includes all 150 homes in the area. It was unknown how many residents have stayed behind, but officials are urging everyone to leave immediately.

Pre-evacuation warnings remain for people living east and south of U.S. 93 between the intersections with Montana 28 and Lake Mary Ronan Road.

Red Cross Evacuation Centers are in place at Polson High School and Somers Middle School. A community meeting was planned for Wednesday at 7 p.m. at the Elmo Pow Wow Grounds.

More firefighters joined the attack Tuesday, bringing the total personnel on the scene to 375. The crews are being managed by John Thompson’s Northern Rockies Team 7.

On Tuesday, firefighters on the ground with aerial support were able to establish control lines on the east and west flanks. The southern edge along Montana 28 remained contained.

On the north flank, crews were working to build fire lines and contain spot fires in hay fields. Engines patrolled the fire overnight.

The cost to fight the fire so far is estimated at $3.7 million.

MEANWHILE ON the Mission Mountains north of St. Ignatius, the Redhorn Fire grew to 144 acres. The lightning-caused fire was burning in heavy timber in steep and rough terrain.

About 42 firefighters were assigned to the fire. Air resources were dropping water on the fire as conditions allowed.

In northern Lincoln County, the Weasel Fire was estimated at 155 acres and 0% contained on Wednesday morning.

The lightning-caused fire is burning about 14 miles northeast of Eureka in the Ten Lakes area. About 70 firefighters are assigned to the blaze.