Winds caused a flare-up Monday, forcing officials to postpone plans to set the backfires to create a buffer south of the ferocious fire to protect the foothill neighborhoods of the San Gabriel Valley.
The winds were expected to gust up to 25 mph in the late afternoon.
"It's keeping this thing volatile," U.S. Forest Service spokesman Stan Bercovitz said.
The 14-day-old fire has blackened 160,357 acres, or 250 square miles, as it burned deeper into the wilderness. It was 60 percent contained.
The fire has killed two firefighters, injured 11 others and destroyed 78 homes, two commercial buildings and dozens of outbuildings. The fire was expected to be contained Sept. 15.
Los Angeles County sheriff's and fire investigators were continuing a homicide investigation into the fire. Officials have said the cause of the fire was arson but have released no other findings.
County firefighters Tedmund Hall and Arnaldo Quinones were killed in a truck accident Aug. 30 while seeking an escape route for their inmate fire crew after flames overran their camp.
Sheriff's spokesman Steve Whitmore said the men's vehicle was airlifted off a mountain and taken to a secure location Monday so investigators could analyze it. The examination of the site where the fire started near the Angeles Crest Highway has wrapped up.
Meanwhile, the temporary city that sprang up to house, bathe and feed about 4,600 firefighters was moving Tuesday from a large park in the Lake View Terrace neighborhood of Los Angeles to another park near Irwindale to the east, closer to the active fire.