Evacuations were ordered for about 300 people near the mountain community of Wrightwood east of Los Angeles due to a brush fire that grew to nearly 1,000 acres.
Firefighters worked through the night, fighting the flames from the air and on the ground in San Bernardino County. As of Tuesday morning, the fire was 35% contained and has burned 990 acres.
The increase from 939 acres earlier in the day was due to updated mapping data.
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Evacuations were ordered for about 300 residents in the area over the weekend.
Those living in the area between Highway 2 and Lone Pine Canyon Road, as well as the area from Wright Mountain Road to Sheep Creek Drive are required to evacuate. Evacuation orders are also in place along Desert Front Road and Wild Horse Canyon.
An evacuation center has been established at Serrano High School, at 9292 Sheep Creek Road, Phelan, CA 92371. The Red Cross is on the scene.
Evacuations began Sunday afternoon, with law enforcement officers knocking on doors to inform residents of the danger posed by the fire.
The Sheep Fire was first reported to the Angeles National Forest Emergency Communications Center around 6:36 p.m. on Saturday. It was initially just a quarter of an acre in size.
By 1:30 p.m. Sunday, the fire was up to 45 acres in size.
"The fire is becoming more active, with some torching / burning of trees in the interior," a spokesperson for the Angeles National Forest division of the U.S. Forest Service said in a status update around 1:30 p.m.
"Crews are actively working along the perimeter of the fire, while fixed-wing operations have concluded for now," the statement continued.
By 3:30 p.m., the fire was up to 150 acres, and by 4:15, it had exploded to 775 acres in size.
"Fighting this fire has been especially challenging due to dense vegetation, steep terrain, and high and erratic winds," the U.S. Forest Service said in a status update.
The cause of the fire remains under investigation. Several agencies are working together to put out the blaze.
There are 673 firefighters battling the fire, including staff from the Bureau of Land Management.
A satellite image showed smoke from the fire drifting east Sunday.
Fuel moisture levels are well below historic averages in parts of Southern California, meaning vegetation is drying out more quickly this year.
Dry vegetation is one significant factor in the spread of wildfires. The state is coming off one of its driest late winters on record, leaving hillsides covered in dry brush.
California continues to face longer wildfire seasons as a direct result of climate change, according to CAL FIRE.
"Extended dryness originating from January is expected to continue into the spring with little precipitation, leaving most of the state in moderate to extreme drought conditions prior to summer," the state's firefighting agency said in a 2022 fire season outlook.
"These continued dry conditions, with above normal temperatures through spring, will leave fuel moisture levels lower than normal, increasing the potential for wildland fire activity."