Surging king tides could combine with deadly sneaker waves in PNW

PORTLAND, Ore. (KOIN) — The seasonal king tides forecast to swamp Oregon and Washington’s coastline from Nov. 25 to Nov. 27 will pair with a heightened risk of sneaker waves. The combo will create especially dangerous beach conditions through the Thanksgiving weekend.

Local National Weather Service Meteorologist Hannah Chandler-Cooley told KOIN 6 News that the Pacific Northwest will see a moderate threat of sneaker waves on Thanksgiving. Beach conditions will worsen over the weekend as a “high” threat of sneaker waves will exist at the same time as the seasonal king tides — the highest tides of the year.

<em>In this Jan. 11, 2020 photo an extreme high tide rolls in and floods parts of the harbor in Depoe Bay, Ore. during a so-called “king tide” that coincided with a big winter storm. Amateur scientists are whipping out their smartphones to document the effects of extreme high tides on shore lines from the United States to New Zealand, and by doing so are helping better predict what rising sea levels due to climate change will mean for coastal communities around the world. (AP Photo/Gillian Flaccus)</em>

Mountain snow, freezing rain possible during Thanksgiving travel days

King tides occur when the alignment of the sun and moon combine to add extra pull on the Earth, causing its oceans to swell. During a king tide, water levels can be half-a-foot or more above the highest daily tide average. These exceptionally high tides can flood coastlines — especially when combined with stormy weather.

Sneaker waves are powerful rogue waves that unexpectedly surge past tidelines. The potentially deadly waves can carry heavy objects like logs and sweep beachgoers off their feet, dragging them into the icy water. KOIN 6 Meteorologist Josh Cozart warns that a sneaker wave hitting a beach during a king tide would create an added level of danger.

“The sneaker wave and king tide collision this weekend is great for ocean viewers, but also poses some of the biggest risks of the year to those heading to the coast,” Cozart said. “The first rule is to never turn your back on the ocean when heading to the coast. King tides make for a shallow beach, helping to push unsuspecting waves even farther onshore.”

Oregon’s 2023-2024 king tide forecast:

  • November 25 – 27, 2023

  • December 13 – 15, 2023

  • January 11 – 13, 2024

  • February 8-10, 2024

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