King Tides are coming: Here’s when western Washington should worry

November marks the start of King Tide season. The winter months are when the marine waters of western Washington get their highest astronomical high tides of the year.

The next period of King Tides rises during the first weekend of December.

What is a King Tide?

King Tides are the highest tides that occur during each winter season when the sun, moon, and Earth are all aligned. Earth revolves around the sun in an elliptical orbit, and during the winter season, the planet is closer to the sun in that orbit, producing a greater gravitational pull from the sun. When the moon is aligned with the sun, both produce a stronger gravitational pull on the oceans, resulting in King Tides.

King Tides by themselves can cause some minor tidal overflow flooding of low-lying coastal areas of western Washington. But if a storm with lower atmospheric pressure coincides with a King Tide, then a higher tidal anomaly, meaning higher tides than predicted for that date and time, can occur. And if the storm is also producing strong winds, wave action can result in greater coastal flooding damage.

Previous King Tide events

In late October 2003, such a King Tide and strong wind event occurred. The most memorable damage happened at Ivar’s Restaurant next door to the former Mukilteo ferry terminal.

Another similar King Tide event occurred on December 17th, 2012. A number of places throughout the Puget Sound coastal region suffered high water and wave action damage, including water and logs into homes, not a desired holiday gift under the tree.

In recent years, coastal communities like Westport have had tidal flooding in downtown streets, even without a strong storm present. In late December 2022, a King Tide combined with heavy amounts of rainfall in Olympia resulted in jellyfish floating onto downtown streets. At the same time, the lower parts of South Park in Seattle also suffered significant tidal flooding.

Future King Tide periods in Seattle, Everett

In the next few months, there will be several King Tide periods noted on forecast tide charts.

For Seattle, tidal overflow coastal flooding usually starts at around 13.5 feet. Here are the upcoming King Tide periods of at least 12.5 feet:

• December 5 through 9.
• January 3 through 8.
• February 2 through 4.

The highest predicted tide of the winter season for Seattle will be on January 5 at just under 13 feet. December 6 and 7 will also both be close at nearly 12.9 feet.

For Everett, greater than 12.5-foot high tides include:

• December 5 through 8.
• January 2 through 6.
• February 2.

The highest predicted tide of the season for Everett will be on January 4 at 13.0 feet.

King Tide events combined with stormy, windy weather are likely to occur in the future.

Preventing damage

Shoreline property owners can take action now to help avoid damage, such as reinforcing seawalls and other protective structures.

Stay informed ahead of time for potential western Washington coastal flooding by monitoring weather.gov/seattle/, your local NOAA Weather Radio station, or local media, including KIRO Newsradio.

Ted Buehner is the KIRO Newsradio meteorologist. Follow him on X and Bluesky. Read more of his stories here.