FRAZIER PARK, Calif. – Cooler temperatures and lighter winds gave hundreds of firefighters a breather from a wildfire that has blackened hills near Interstate 5 north of Los Angeles.

The fire that broke out Wednesday in the Los Padres National Forest charred 3,800 acres of dry, thick trees in torrid conditions.

But despite a 20-degree dip in heat and a heavy aerial effort to beat back flames, it was still just 25 percent contained Thursday night.

Fire officials blamed very difficult, rugged and tough-to-reach terrain along with persistent winds of more than 20 mph that are expected to continue through the night into Friday.

“It’s definitely gusty, but we’re lucky, the winds are blowing away from homes,” Kern County Fire Department spokesman Corey Wilford said. “It would be better if we didn’t have winds at all though.”

Thursday’s lower temperatures are expected to persist into the weekend.

The fire has burned in mostly populated areas and threatened no homes or buildings.

The fire started early Wednesday afternoon for reasons that remain under investigation. It initially burned thick brush, seasonal grasses and sage but then moved into the trees.

The cooler weather helped firefighters overnight clear brush and create breaks in hopes of slowing the blaze.

Efforts on Thursday were focused on the southern edge of the fire.

The cause of the fire is under investigation.