The National Weather Service warned Saturday of a threat of sneaker waves on the Oregon and Washington coast through at least Sunday evening.

Sneaker waves, which often accompany stormy weather, arrive unexpectedly and with enormous force – sometimes reaching areas away from the beach that appear far from the tidal zone. That makes them especially deadly and, forecasters say, requires extra vigilance.

Two Portland children died earlier this month when they were swept away by a sudden tidal surge south of Cannon Beach. There have been several similar tragedies on the coast in recent years.

The weather service warned of sneaker waves that could “create potentially life-threatening conditions in the surf zone. Caution should be used when in or near the water. Always keep an eye on the waves, and be especially watchful of children and pets.”

-- Mike Rogoway | mrogoway@oregonian.com | twitter: @rogoway | 503-294-7699

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