Row upon row of razed houses were visible from the helicopter as firefighters continued to contend with the blaze, which had burned 13,690 acres and was 3% contained as of Friday morning.
Fire officials said approximately 7,801 structures were believed to be "damaged or destroyed," with nearly 1,000 structures destroyed.
Gusty conditions persisted in the mountains Thursday, hampering aerial firefighting efforts as flames crawled through treetops and thick vegetation toward the peak of Mount Wilson, threatening the observatory and a series of broadcast towers critical for local television and radio outlets.
On Friday morning, Los Angeles County Fire Chief Anthony Marrone said some 1,603 personnel were assigned to the firefighting effort, with Friday's priority structure protection and fire line construction to increase containment on the east, north and west flanks.
Pasadena Humane Society treating injured pets and wildlife amid fires
A red flag warning remained in effect until at least 6 p.m. Friday.