Silverado fire in Cleveland National Forest

An Orange County Fire Authority helicopter takes on water from the drought-stricken Irvine Lake before making a water drop on a brush fire near homes on Silverado Canyon Road.  (Allen J. Schaben / Los Angeles Times)

A sign thanking firefighters is posted along Silverado Canyon Road as crews battle the fire in the Cleveland National Forest.  (Allen J. Schaben / Los Angeles Times)

An Orange County Fire Authority helicopter makes a water drop on a brush fire near homes on Silverado Canyon Road.  (Allen J. Schaben / Los Angeles Times)

Orange County firefighter Duke Juarez takes a break after hiking up a steep hillside in high heat while extinguishing hot spots near homes on Silverado Canyon Road as crews battle the Silverado Fire.  (Allen J. Schaben / Los Angeles Times)

An inmate firefighter hand crew hikes up a steep hillside in high heat while extinguishing hot spots in Silverado Canyon.  (Allen J. Schaben / Los Angeles Times)

An Orange County Fire helicopter makes a water drop on a brush fire in Silverado Canyon.  (Allen J. Schaben / Los Angeles Times)

Inmate crews battle the heat and the fire as they join the more than 280 firefighters battling a blaze in Silverado Canyon.  (Mark Boster / Los Angeles Times)

Hand crews douse hotspots on a steep hill in Silverado Canyon.  (Mark Boster / Los Angeles Times)

More than 280 firefighters are aided by water-dropping helicopters and fixed-wing aircraft as they battle a 1,300-acre fire in Silverado Canyon.  (Mark Boster/ Los Angeles Times)

More than 280 firefighters are aided by water dropping helicopters and fixed-wing aircraft as they battle a 1,300-acre fire in Silverado Canyon.  (Mark Boster / Los Angeles Times)

An inmate fire crew member wipes the sweat from his brow as he takes off for the fire line in Silverado Canyon.   (Mark Boster / Los Angeles Times)