Wildfires on Monday destroyed three homes on Highway 116 west of Cotati and one home in Comptche, with the Mendocino County blaze burning at least 200 acres.
"This was probably one of the worst days ever to have a fire with the extreme heat and wind," said Chief Larry Tunzi of the Comptche Volunteer Fire Department.
The fires broke out on a day of near-record temperatures across the North Coast, hitting 101 degrees in Santa Rosa and 105 in Cloverdale. The hot winds stoked the fires and sent burning embers flying across roads and into trees.
Three homes were destroyed on the north side of Highway 116 near Stony Glen Lane and Stony Point Road after a fire reportedly was triggered by vehicle backfire.
"The real key was the afternoon wind coming from the west," Cal Fire Division Chief Eric Hoffmann said.
Initially reported at 4:05 p.m. as a "huge grass fire" on the south side of Highway 116, the fire within an hour jumped north across the road and engulfed several homes.
A witness told authorities an old pickup backfired and started the fire, CHP Officer Jon Sloat said. Fire officials located the driver and were investigating, Hoffmann said.
The fire forced authorities to close Highway 116 until about 7:40 p.m. By then, the fire had been contained by firefighters.
In Comptche, seven family members, including at least three children, were displaced when their home near Flynn Creek Road and Comptche Ukiah Road was destroyed by a fire that by Monday night had spread to 200 acres and was 5 percent contained.
Cal Fire reported the fire was threatening 70 structures. But Tunzi said the threat had diminished because the fire was burning eastward in remote timberland.