The fire in the Summit area north of Santa Cruz was threatening about 150 homes and about 60 of them were under an evacuation order expected to last at least until Monday, said Cherie Alver, a spokeswoman for the California Department of Forestry and Fire Protection.
The fire had destroyed a trailer and two outbuildings and burned about 600 acres by nightfall Sunday, authorities said. It was 20 percent contained. About 100 businesses also were threatened.
Despite recent rains in the area that brought worries of mudslides, fire officials said fire-friendly weather made a small blaze surge.
"We had some pretty strong winds up here this morning. It was howling," Loma Prieta Fire Chief Alex Leman told the San Francisco Chronicle. "That gave the fire quite a bit of energy."
The fire started at about 3 a.m. on a ridge in Santa Clara County and quickly spread down into a canyon and into Santa Cruz County. The cause remained under investigation, Alver said.
The winds abated late in the day and allowed firefighters to establish some containment lines, but they were expected to pick up again by Monday morning, Battalion Chief Jim Crawford said.
More than 1,000 firefighters and 15 water-dropping aircraft were expected to be taking on the blaze by daylight, fire officials said.
The fire was burning near an area where a wildfire last year destroyed 29 homes and threatened the Mount Madonna retreat center.