Footage of an actual sneaker wave south of Coos Bay, Oregon.

Eureka’s National Weather Service Office has issued a sneaker wave warning for the North Coast starting now and ending Friday afternoon.

The NWS reports that the greatest risk of sneaker waves will occur between Wednesday night and Thursday night along west and northwest facing beaches.

“Do not let the ocean fool you,” the NWS stated in its warning. “Long period waves can generate lulls of wave activity making the ocean look deceivingly calm and draw people closer to the water. These lulls end with a large set of breaking waves that will wash much farther up beaches, possibly knocking you down. Plan on keeping a safe distance from the surf.”