SAN FRANCISCO (AP) – A storm brought strong winds, periods of heavy rain, snow and high surf to California on Sunday, the fourth day of wet weather that has prompted road and school closures and left an officer injured.

Dry conditions and warmer weather are forecast for Monday.

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A California Highway Patrol officer was in serious but stable condition Sunday after being struck by an out-of-control vehicle as he provided traffic control in snowy conditions on a mountain pass, the CHP Truckee office said.

The accident Saturday led authorities to temporarily close a portion of Interstate 80 near Donner Summit, a treacherous road in the Sierra Nevada in the northeastern part of the state that has been battered by a series of winter storms. The weather was bad enough that the officer had to be taken to the hospital by ambulance instead of by helicopter, CHP Lt. Sven Miller told the Sacramento Bee.

More than 1 foot of snow fell in the area overnight and up to 3 feet were expected in the higher elevations of the Sierra Nevada through Monday, the National Weather Service reported.

In counties north of San Francisco, rivers swelled and the flood risk was high. About 8 ½ inches of rain fell during a 72-hour period in the unincorporated town of Venado in Sonoma County.

Water from the rain-swollen Sacramento River was spilling Sunday over a 33.5-foot-high concrete wall and into a bypass built to divert flood water.

The overflow is expected to reach a depth of 3 feet Tuesday then start receding, said Robert Hartman, a hydrologist with the National Oceanic and Atmospheric Administration.

It’s the first time water that has spilled over the so-called Fremont Weir crest and into the Yolo bypass since 2012. The nearly 2-mile-long concrete wall is located about 8 miles northeast of Woodland.

The bypass is an expanse of farmland and natural habitat that stretches from Sacramento to Davis and was created a century ago.

A portion of California Highway 1 in Mendocino County was closed where slides nearly toppled a California Department of Transportation dump truck with an employee inside.

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The truck hit a guardrail – stopping its fall – and landed at a 45-degree angle. No one was injured.

In the East Bay, a landslide near the Moraga Country Club prompted at least two homeowners to evacuate from their hillside homes. Tim Alford told the Contra Costa Times he noticed cracks at the foot of his home on Tuesday, and two days later his decks had collapsed.

He and another neighbor, Darlene Martel, hired a geologist.

“He came and told me: ‘I would not sleep here,'” Martel said.

Powerful rains also slammed the central part of the state, flooding streets in Fresno and briefly shutting down the airport there.

The storm dumping rain in much of Northern California is expected to weaken as it moves south, though the southern part of the state could see scattered showers or drizzle, and beachgoers were warned of powerful surf along the Central and Southern California coast.

Waves up to 8 feet could pound beaches for most of the day Sunday, the National Weather Service said.

A high surf advisory is in effect in Santa Barbara, Ventura and Los Angeles counties.

Meanwhile a wind advisory has been issued for some coastal areas and in the mountains and high deserts.

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Copyright 2016 The Associated Press.