Low humidity and high temperatures accompanied by a seasonal blast of Santa Ana winds have been keeping Southern California fire agencies on alert.
The National Weather Service said dry, gusty winds would continue Saturday before dying down towards the end of the weekend.
Firefighters moved quickly Friday to control small brush fires across the region.
A blaze that burned through patchy brush in the Fontana area below the Cajon Pass was held to about 10 to 15 acres, said San Bernardino County fire spokesman Eric Sherwin. More than 150 firefighters were brought in from many agencies. No structures were damaged.
Division Chief John Salvate said there had been concerns the fire could reach some homes due to sustained winds of 25 mph and 35 mph and gusts of up to 50 mph earlier in the day.
In Los Angeles County, firefighters held a fire to 1 acre along a road in the Santa Monica Mountains near Malibu.
Crews successfully contained a slow-moving brush fire that spread over about 2.5 acres on a hillside in eastern San Diego County.
The Santa Ana winds, which blow through in the fall, bring high fire danger because their powerful gusts can whip flames into infernos. The Santa Anas have been involved in many of Southern California's most destructive wildfires.
The winds are spawned by surface high pressure over the interior of the West that sends a cold, dry air mass toward Southern California. The air then warms and speeds up as it descends through mountain passes and canyons and rushes toward the coast and offshore.
Forecasters said the high pressure will slowly weaken through Sunday, gradually reducing wind speeds. A high wind warning was reduced to an advisory, but forecasters said there was a slight chance of an isolated gust to 58 mph or greater in some passes and canyons.
A 66 mph gust was reported before dawn Friday, the weather service said.
State and local fire agencies had prepared for Thursday's arrival of the wind event by staffing additional fire engines and positioning them in strategic locations.
With the improving outlook, Los Angeles city and county deactivated their emergency operations centers but were continuing to monitor the situation, the county Office of Emergency Management said in a statement.