Arriving flights were being delayed up to 45 minutes Saturday afternoon, and about 12 flights had been canceled because of a change in the direction of prevailing winds, Wilson said.
With the wind coming from the south instead of the west, only two of the airport's four runways were being used for takeoffs and departures, Wilson said.
"It's an unusual wind for us," he said.
North of San Francisco, more than 6 inches of rain fell Friday in the tiny Sonoma County community of Venado. And with a second storm approaching, officials were paying close attention to the rising levels of the Russian River.
The river was expected to peak just below "monitor stage" on Christmas Eve, said National Weather Service hydrologist Allan Takamoto. That's about 3 feet below flood stage but high enough that officials had a "heightened awareness of what's going on," Takamoto said.
The heavy rain caused problems on local highways, forcing officials to close a section of Highway 128 in Napa County near Lake Berryessa.
In Mendocino County, Highway 162, which connects the community of Covelo with Highway 101, was closed because of a washout.
Along the beaches, waves up to 16 feet were expected. Forecasters were urging people walking along beaches or jetties to watch for large breaking waves.
Associated Press writer Martin Griffith in Reno, Nev., contributed to this report.