A small, lingering brush fire in the backcountry of Yosemite National Park exploded into a large wildfire Sunday, prompting park officials to evacuate hikers by helicopter from Half Dome and the wilderness above Yosemite Valley, park officials said.
By Monday morning, the wildfire was estimated at 2,582 acres, park officials said. The blaze was labeled the Meadow fire.
About 100 hikers and backpackers were evacuated from the area surrounding Half Dome, said Yosemite National Park spokeswoman Kari Cobb. The campers are being taken to different locations in Yosemite Valley and provided alternatives to continue their stay, she said.
On Sunday night, Cobb said a helicopter is flying around in the backcountry areas searching for additional hikers that park officials might not be aware of.
Officials have closed trails from the top of Nevada Fall to Merced Lake, including trails leading to that area. They have also closed off the trail from Sunrise Lakes Trailhead to Sunrise Lakes and Sunrise Lakes High Sierra Camp, as well as the trails from the camp to the trail along the Merced River east of Little Yosemite Valley.
But all roads leading into the valley remain open, Cobb said. Smoke has not affected that area, instead rising up into the air.
The wildfire was started by lightning in mid-July adjacent to Mt. Starr King, said Tim Ludington of the National Park Service.
Strong winds and hot temperatures ignited a spot fire that dropped into Little Yosemite Valley and crossed the Merced River. Helicopter crews noticed the spot fire about 12:30 p.m. Sunday, a park official said.
"We just got unbelievable crazy winds and unexpected hot conditions," Ludington said. "The fire behavior totally changed. There is a huge plume."
Ludington said the fire is expected to keep growing.
While the fire was originally allowed to burn for forest restoration and other objectives, firefighters are now working to fully suppress the flames, park officials said.
On the scene Sunday afternoon were seven helicopters, three air tankers and one air attack plane, according to a Yosemite fire information update posted online. Additionally, six hotshot crews of 20 people each arrived Sunday evening along with Yosemite fire crews. It takes firefighters about a day to hike into the remote area.
Meanwhile, the 300-acre Bridge fire east of Mariposa was 70% contained Sunday evening and all evacuation orders have been lifted, according to Cal Fire and the Mariposa County Sheriff's Office.