Orange County wildfire 20% contained, but heat could slow progress

Firefighters slowed the growth Sunday of the blaze burning in the rugged hills of Orange County’s Cleveland National Forest, but officials warned that the fire could become more volatile as winds pick up and temperatures rise into the triple digits.

Nearly 1,100 employees from federal, state and county fire agencies are working to control the blaze, which is burning in steep canyons covered in bone-dry chaparral. Crews are using nine water-dropping helicopters and seven bulldozers to dig fire lines and hold back flames on rocky ridges near Corona.

The fire grew by fewer than 100 acres overnight, and was 20% contained by mid-morning Sunday. Officials expect the fire to continue to spread to the east and north into craggy, hard-to-reach areas of the forest.

“In Southern California, in this type of environment, the fuels are very flashy and very dry,” said Jake Rodriguez, a spokesman with the U.S. Forest Service. “Things can change very quickly.”

No homes have been damaged in the fire, which was first reported Friday morning. Mandatory evacuations are still in place for the 217 homes in the eastern portion of Silverado Canyon.

The South Coast Air Quality Management District on Sunday issued a smoke advisory for Orange County. Residents of Saddleback Valley, Corona, Lake Elsinore and Capistrano Valley should stay inside and avoid vigorous activity, according to the alert. Residents have been told to run their air-conditioners and avoid burning firewood.

Six firefighters have been treated and released from local hospitals, three for heat-related injuries, Rodriguez said. He added dehydration and exhaustion will become more serious issues for crews as they face 102-degree heat on the fire lines.

“Heat injuries are not something that you can mess around with,” Rodriguez said. Supervisors are encouraging fire crews to take breaks and drink fluids, and helicopters will be dropping cases of water and Gatorade.

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