Hot, dry Santa Ana winds increased Saturday as crews battling a three-week-old wildfire in Los Padres National Forest rushed to carve fire breaks before the fiercest gusts arrived.

"It is blowing ferociously. We expect a lot more acreage to go," Ventura County fire Capt. Barry Parker said. Winds were gusting to 52 mph in the area about 75 miles north of Los Angeles, officials said.

No imminent threat was reported to homes. But 10 homes were evacuated, and hundreds of people in communities about 10 miles from the fire's edge were urged to be ready to evacuate if the winds from the northeast set the flames racing.

The National Weather Service issued a red flag warning for extreme fire conditions through Sunday in the area. Forecasters said gusts as high as 70 mph were possible during the weekend.

Such conditions could drive the blaze in mile-long leaps along ridges and steep canyons, with flames spreading as fast as 11 mph, said Larry Comerford of the U.S. Forest Service.

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A light, moist wind from the south had calmed the fire for much of the week. Crews used the time to burn chaparral and wrap isolated homes in protective material. Fire trucks waited in some driveways to protect dwellings. Parker said more than 20 aircraft were "painting the hills with fire retardant" but would have to be grounded if the winds became too powerful.

The fire along the border of Ventura and Los Angeles counties doubled in size to about 80,000 acres, or 125 square miles, when Santa Ana winds kicked up a week ago. The fire began on Labor Day and has burned 116,971 acres, or nearly 183 square miles. It was nearly 40 percent contained.

More than 3,000 firefighters were battling the blaze, which has cost $31.7 million to fight.

Elsewhere, crews mopped up two smaller fires in forests to the south.

A 2,730-acre fire in San Bernardino National Forest was fully contained Saturday. A fire in Angeles National Forest north of Los Angeles was fully contained Friday after burning 113 acres.

In northern California, calmer weather helped firefighters control and extinguish a series of fires that destroyed three homes, 15 barns and dozens of cattle. Officials lifted an evacuation order for more than 100 residents near Zamora, said Mike Chandler, acting fire coorditor Yolo County.