UPDATE:

The Silverado Canyon wildfire was 10 percent contained as of 2:30 p.m., officials said. The size of the fire was adjusted downward today to 1,500 acres, according to Jake Rodriguez of the U.S. Forest Service.



More than 730 firefighting personnel are on the scene.

Thirty houses remain under mandatory evacuation as a precaution, said Tauhir Jones, spokesman for the Cleveland National Forest. About 106 residents are still are without power after 436 properties lost power midday Friday.

Irvine Regional Park is serving as a fire camp for firefighters today and will be closed to the public.

A heat advisory in effect for all of Orange County; In Silverado Canyon, temperatures could reach about 105 degrees.



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A brush fire in Silverado Canyon burned out of control Friday, blackening more than 1,600 acres in steep terrain, heavy brush and near triple-digit heat, forcing mandatory evacuations of about 30 homes.

The fire grew rapidly after breaking out about 10:30 a.m., sweeping up the north side of Silverado Canyon, away from homes and into the remote expanses of the Cleveland National Forest. Firefighters spent the day digging in lines, hoping to starve the blaze of fuel before it reached the top of a canyon ridge.

The fire was moving slowly by late Friday night as it crested the ridge. Coordinated water and fire-retardant drops ended when the sun went down. Crews were settling in to continue trying to contain the flames overnight, aided by one aircraft monitoring the progression from above.

Strike teams were guarding the homes at the bottom of the canyon in case the fire decided to backtrack. The Orange County Sheriff’s Department announced mandatory evacuations at 6 p.m. for all homes east of 30500 Silverado Canyon Road.

Authorities described the evacuations as precautionary, as winds that blow up the canyon generally reverse and blow down the canyon at night. Winds were calm during the day, and were expected to remain light and moderate during the night. It’s believed dozens of people spent the night out of their homes.

A combination of falling temperatures, rising humidity and changing winds was expected to aid firefighting efforts overnight, Orange County Fire Authority Battalion Chief Mike Petro said.

Crews hoped to keep the blaze contained southwest of the Main Divide Road, southeast of Ladd Canyon Road and north of Silverado Canyon Road, Petro said.

Three firefighters sustained minor heat-related injuries, authorities said.

Silverado Canyon Road was closed to most traffic at Santiago Canyon, although residents were allowed deeper into the canyon. East of that, the road was expected to remain closed into the night, officials said.

The American Red Cross opened an evacuation center at El Modena High School, 3920 E. Spring St., in Orange.

Air-quality regulators warned that smoke from the fire could make the air unhealthy in the Saddleback Valley area and in parts of Capistrano Valley, Corona, Norco and Lake Elsinore. The column of dull-white smoke towering thousands of feet into the air could be seen across Orange County.

The fire apparently started in the backyard of a canyon home, although the cause remains under investigation, OCFA Capt. Larry Kurtz said. It exploded through hundreds of acres within hours.

“There was a weird, red glow to the sky,” said Connie Nelson, who lives in Silverado Canyon and heads a community group called CanyonWatch. “I immediately knew what it was and started calling people to warn them.”

Nelson spent the rest of the day helping to move a dozen horses and a goat. By Friday afternoon, she said, ash and smoke were drifting over her home, and the skies were abuzz with helicopters battling the blaze.

Fire officials said they had no containment on the fire as of late Friday night.

At least 280 firefighters from the OCFA, U.S. Forest Service, California Department of Forestry and Fire Protection and the Orange and Anaheim fire departments were on the ground.

The fire announced itself Friday morning to Silverado Canyon resident Doyal Teel with wisps of smoke curling over the hill behind his home. He called 911. When he looked again, flames were coming over the ridge. And then the entire hillside was engulfed.

“I hope it doesn’t switch around when the offshore breeze kicks up,” he said Friday evening. “I’m concerned, but I’m not super worried. I’ve got everything laid out in case it catches. I’ve got my truck packed with photos, documents and crates for the dogs.”

“When you look at where we live, most of the time it’s nice,” he added, “unless a fire or flood intrudes on your serenity.”

In nearby Modjeska Canyon, Jim and Diane Carter watched the fire from a lookout tower at their house. They added the tower when they rebuilt after the 2007 Santiago Fire destroyed their iconic, 4,000-square-foot geodesic dome house.

Jim Carter estimated that the fire was about five miles away as a radio in the tower squawked with reports from Modjeska, Silverado and Santiago canyons.

“But you never can tell what the wind will do,” he said. “We’re definitely a little concerned.”

Contact the writer: 714-796-7767 sschwebke@ocregister.com Twitter: @thechalkoutline