Updated

Strong Santa Ana winds barreling through Southern California early Monday fanned fires, knocked out power to 77,000 utility customers and blew down tree branches.

Fifteen La Canada Flintridge homes were evacuated before an eight-acre blaze ignited at 2:35 a.m. by a fallen power line was contained 15 miles northeast of Los Angeles, said Los Angeles County fire Capt. Mark Savage.

To the west, a wind-driven fire destroyed a home and damaged five others in Tujunga, a foothill section of Los Angeles. Three people were treated for minor smoke inhalation. Authorities said they were investigating whether downed power lines sparked the blaze.

Winds of 40 mph, with even higher gusts, drove the La Canada Flintridge fire, preventing use of water-dropping helicopters. One of the 100 firefighters on the lines suffered a minor eye injury. Firefighters remained wary.

"Until there's absolutely no embers to blow, there's still concern," Savage said.

High winds arrived Sunday across a broad swath of Southern California from the coast northwest of Los Angeles to counties east and south. The winds, with gusts near 70 mph, were created by high pressure over the northern Great Basin and low pressure off the coast of Southern California, the National Weather Service said.

"Red flag" warnings were issued for many areas through 6 p.m. Tuesday because of the combination of wind and low humidity levels, which increase fire danger.

About 100 Southern California Edison lines went down Sunday and Monday, and some 62,000 customers lost power, Edison spokesman Steve Conroy said. Most outages were in San Gabriel Valley foothills and communities farther east. The Los Angeles Department of Water and Power reported 15,000 customers lost power overnight.

The powerful winds uprooted trees and littered roadways with debris. A large oak tree fell on a house in Pasadena, and a small brush fire damaged a home in Upland.

It was a white-knuckle ride for many Southern California commuters, who had to grip steering wheels with both hands to keep vehicles in traffic lanes. Streets were littered with palm fronds, tree branches, trash cans and overturned newspaper racks.

Pilots taking off at John Wayne Airport in Orange County, where gusts reached 30 mph, were heading east to take advantage of the winds' lift, rather than departing to the west. Boaters were warned to be careful entering and exiting the harbors at Dana Point and Newport Beach.

In rural San Diego County, high winds prompted Mountain Empire Unified School District to cancel classes on Monday, said Debbie Minard in the district's business office. The district, along the eastern edge of the county near the U.S.-Mexico border has about 1,700 students.