The second-alarm wildfire was reported shortly before 2 p.m. near Templin Highway and the 5 Freeway, fire officials said. It started near the shoreline and then quickly spread to the Angeles National Forest.
The flames burned medium-to-light brush, with the acreage at 5 as of 3 p.m. The blaze spread to 1,000 acres and was 10 percent contained by the evening.
Lake Fire Update: 1000 acres have burned, 2 outhouses near a picnic area burned down. pic.twitter.com/oD99fZ1FWF— Melissa MacBride (@abc7melissa) June 18, 2017
No evacuations were issued, fire officials said. Two outbuildings near a picnic area burned down in the path of the blaze.
"Prior to our arrival, (the outbuildings) were consumed by the fire. The low, flashy fuels were able to get to them quickly," L.A. County firefighter Richard Licon said.
The movement of the blaze pushed it into the Angeles National Forest, where at least 195 firefighters were working to put it out.
Three helicopters and six fixed-wing aircrafts fought the fast-moving blaze from the air. Firefighters said the winds are low, which kept the speed of the fire slow, but they dealt with temperatures in the 90s.
Several boats were out on the lake at the time the fire broke out. They remained on the waters at a safe distance as they watched firefighters and crews work on the blaze.
No injuries were reported.
Firefighters will remain overnight in the hopes that the calmer winds and cooler temperatures can slow the progression of the blaze.
The recreational area will be open for Father's Day, officials said.
The cause of the fire was unknown, but investigators said it started in a picnic area where campers can barbeque.