People living in Northern California are being warned to stay away from the ocean this weekend as the National Weather Service says waves could reach up to 50 feet in some areas.

The NWS issued a high surf warning from 9 a.m. Sunday to 9 p.m. Monday. They’re calling it the largest wave event this season.

“A High Surf Warning indicates that dangerous, life-threatening waves will impact the shoreline,” the NWS notice said. “It is advised that people remain off of and away from the shoreline during this event.”

Our sister station KRON reports a series of storms will make its way across the area around the same time, bringing up to three inches of rain to some areas.

The largest waves are expected to arrive Sunday night through Monday morning. The NWS says peak swells are expected to reach 17 to 21 feet at 19 to 21 seconds. Large breaking waves could reach 25 to 40 feet in some areas. Favored break points along the coast could see waves up to or exceeding 50 feet.

The NWS says the waves will lead to increased wave run-up on beaches. Waves are expected to wash over large rocks and jetties.

People are being urged to stay well away from the water because the waves will be capable of sweeping people into the cold, turbulent ocean water.

One tweet from the NWS warned people to “STAY WELL BACK FROM THE OCEAN OR RISK CERTAIN DEATH.”

NBC News reports the swell is expected to lose energy as it moves south. Some spots in Southern California could still see waves up to 12 feet.