SAN FRANCISCO (AP) - Northern Californians are slogging through another day of wet and windy weather as the second storm of the weekend moves through the region.
After a bit of a break in the weather Saturday evening, the National Weather Service is predicting heavy rain and strong winds for the San Francisco Bay area through Sunday.
On the freeways, a high wind advisory is in effect for the San Francisco-Oakland Bay Bridge, the San Mateo-Hayward Bridge and the Carquinez Bridge in Vallejo, meaning people driving campers or hauling trailers are being advised to stay off the bridges.
On Interstate 80 through the Sierra, officials say chains are required on vehicles except four-wheel drives from the Placer County community of Gold Run to the Nevada state line.
The first weekend winter storm system that passed over Northern California proved a nuisance for holiday travelers, but a second, bigger wave of Mountain snow and coastal rains expected early Sunday could make for real problems.
Up to 5 feet of snow is expected in the higher elevations of the Sierra Nevada before by the time the second storm has passed, and the San Francisco Bay area could be seriously doused.
"It's expected to bring some sustained winds, with a possibility of thunderstorms and moderate to heavy rain," said National Weather Service forecaster Diana Henderson.
The first storm drenched the region, dropping more than an inch of rain in Redwood City, about 24 miles south of San Francisco, in a little more than six hours Saturday.
To the east in the Sierra Nevada, Interstate 80, the main route between Sacramento and Reno, Nev., was shut down for about three hours after snowy roads caused several spinouts, but was reopened later in the afternoon, state highway officials said.
Officials said tire chains were mandatory for all vehicles except four-wheel drives on all three major mountain highways between the Sacramento and Reno areas - I-80 over Donner Summit, U.S. 50 over Echo Summit and State Highway 88 through Carson Pass, which was also briefly shut down.
Interstate 5 near the Oregon border was open to cars and truck with chains. It had been shut down late Tuesday for about 12 hours after a 60-car pileup near Yreka then closed again Friday when a storm dropped several inches of snow in some areas of Siskiyou and Shasta counties.
The weather was causing delays Saturday at San Francisco International Airport but was affecting mostly regional flights, airport duty manager Shannon Wilson said.
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.
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