Fire officials are trying to keep the upper hand on the huge wildfire burning north of Los Angeles, but conditions have become unpredictable.

The blaze was 56 percent contained Monday, but plans to set preventive backfires were cancelled when another area began burning.

Incident Commander Mike Dietrich said Monday that the weather didn't cooperate.

The aircraft needed to support the burnout operations had to be diverted to the fire's northeastern flank.

Since the fire began burning Aug. 26, it has blackened 157,220 acres, or 246 square miles, and is now heading deeper into the wilderness.

Damage assessment teams say 78 homes, two commercial buildings and dozens of outbuildings have been destroyed by the flames, and 11 firefighters have been injured.

The fire was expected to be fully contained Sept. 15.