Trees killed by mountain pine beetles are feeding the Big Meadows fire on the west side of Rocky Mountain National Park. The blaze grew from about 3 acres Tuesday morning to as many 400 by the evening, according to the National Park Service.
The fire is about 4.5 miles from the Green Mountain Trailhead in a remote area of the park west of the Continental Divide, and is moving to the northeast toward Nakai Peak.
Authorities believe the fire was started by lightning.
High winds deterred deployment of smoke-jumper firefighters to the area Tuesday afternoon, the park service said.
Five trails are closed in the area: the Onahu Trail, the Green Mountain Trail, the lower Tonahutu Trail, the Tonahutu Spur Trail and the Grand Lake Lodge Spur Trail. All major roads in Rocky Mountain National Park are open, however.