Sailors beware: Waves could reach up to 20 feet by the end of this week. That would be the highest seas since last winter.

The National Weather Service issued a warning Sunday to any mariners that the waters off the Oregon coast could be dangerous.

The waves are expected to climb from 3 to 5 feet to 10 to 12 feet within a few days, with a potential maximum height of 20 feet Thursday through the weekend. For reference, a two-story house is about 30 feet tall.

Gale force winds could reach up 35 miles per hour on Wednesday.

Those conditions would be dangerous for commercial and recreational boaters and fishers.

Last year, waves grew up to 60 feet tall, pummeling the coast and injuring several people.

-- Molly Harbarger

mharbarger@oregonian.com | 503-294-5923 | @MollyHarbarger

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