A drought-driven wildfire burning in an area of the San Bernardino National Forest that hasn't burned in more than 100 years grew overnight to 11,000 acres.
The Lake fire, which is 10% contained, continues to rage in Barton Flats as it consumes thousands of drought-stricken trees and burns east toward forestland, said Lyn Sieliet, a spokeswoman for the U.S. Forest Service. There are no reports of fire in the area in 104 years of record-keeping, she said.
On Thursday, U.S. Forest Service fire officials said the Lake fire is the largest blaze this year in a California national forest.
Heat and low humidity will be troublesome for firefighters who are working to cut 10,000 feet of fire lines around the massive blaze. Temperatures could soar to 100 degrees while low humidity will keep the forest dry.
"The low humidity is a concern for us because we are not getting a good recovery overnight," she said.
Water-dropping helicopters worked Thursday night to put out flames while hand crews trekked into the wilderness to fight the blaze from the ground.
Hot, dry conditions are driving the fire, making the firefight arduous. Winds up to 10 mph are fanning the flames, but the dry conditions are proving to be the challenge.
As the fire scorches grass and timber, more than 1,200 firefighters must navigate through steep terrain and thousands of acres of old growth.
This year, researchers with the U.S. Forest Service surveyed 4.2-million acres of trees in the Cleveland, San Bernardino, Angeles and Los Padres national forests and found that 2 million trees have died because of drought and the invasion of bark beetles. The tiny bark beetle thrives in dry conditions, chewing away at pines and making them brittle.
Flames continue to pose a threat to 150 structures, mostly cabins, nestled in the San Gorgonio Wilderness Area.
The fire erupted at 3:52 p.m. Wednesday near Jenks Lake Road and a cluster of summer camps operated by churches and the YMCA.
Fire crews are using 88 engines, an air tanker and 10 helicopters to battle the moderately fast-burning fire.
The cause of the fire is under investigation.
About 300 people have been evacuated, most were from five camps in the area. Other residents lived in cabins in the areas of Angelus Oaks, Onyx Summit, Barton Flats, Seven Oaks and homes off of Rainbow Lane.
Hiking trails into the San Gorgonio Wilderness were closed because of the fire. The Pacific Crest Trail is also closed from Whitewater Preserve to Onyx Summit.
Jenks Lake Road has been shut down, and Highway 38 is closed between Angelus Oaks to Lake Williams.
While the fire is burning near Big Bear, it is heading east and is not affecting recreational activities at Big Bear Lake, Sieliet said.
Firefighters throughout the state are battling other blazes on dry forestland.
At 200 acres, the Sky fire is burning six miles north of Oakhurst, which is south of Yosemite National Park. Fire officials fear the blaze, started by a vehicle fire on Sky Ranch Road, could swell to 1,000 acres in the next couple of days. Evacuations have been issued for all nearby campgrounds.