Newport, Oregon – A major marine hazard is developing along the Oregon coast as powerful long-period swells build into the region Tuesday, creating extremely steep and dangerous seas from Cape Shoalwater, Washington, to Florence, Oregon, and south to Cape Blanco. The National Weather Service offices in Portland and Medford have issued a Hazardous Seas Warning from early Tuesday morning through Wednesday morning, with wave heights of 11 to 18 feet and occasional sets nearing 20 seconds in period.
According to forecasters, seas will rapidly build through Tuesday afternoon, peaking from 2 p.m. to 11 p.m. along the southern Oregon coast, where north winds of 15 to 25 knots will combine with powerful swells to create extremely rough conditions. The Columbia River Bar will also experience treacherous ebb currents Tuesday evening, with waves as high as 16 feet around 5:30 p.m.
The National Weather Service warns that these seas are steep enough to capsize vessels or damage moored boats. Mariners are strongly advised to remain in port, and commercial operators should consider delaying departures until seas subside Wednesday. Coastal residents should also use caution near jetties and surf zones, where sneaker waves and strong rip currents are likely.
Seas are expected to gradually ease below warning levels late Wednesday, but another system may bring renewed hazardous conditions by the weekend.
