A high astronomical tide (9.37′), along with a strong low pressure system and 22-30 kt southeast winds all combined to give us the third highest (10.98′) of the observed water levels that the Local 20/20 King Tide team has monitored in the last 7 years. The wave run up was also high, estimated at 2.1′, resulting in a total water level that ran up the outer steps at the NW Maritime Center. See analysis below, and at the bottom of the post you will see links to the storm surge tool and other tools used, as well as a link for more detail on the project. The photos from the project are also shared on the MyCoast website (you can zoom in on the map to find the Port Townsend photos.)
If you are interested in exploring some of the tools listed in the slides above here are some links:
- Astronomical Tides: https://tidesandcurrents.noaa.gov/map/index.html, and then select the area of interest.
- Regional storm surge guidance that looks out 7 days is at: https://ocean.weather.gov/Loops/ocean_guidance.php?model=STOFS&area=Northwest&plot=surge&day=99&loop=0#top
- Storm Surge Prediction Tool that looks out ~3 days: https://slosh.nws.noaa.gov/etsurge/index.php?page=stn®ion=wc&datum=mhhw&list=&map=0-48&type=both&stn=watown
- The NOAA Sea Level Rise Coastal Viewer that has some rough information on coastal elevations across the country. It visually shows what areas are inundated at various levels of sea level rise above Mean High Higher Water (MHHW). Here it is for Port Townsend and 3′ of SLR, referenced to MHHW (which is 8.5′ for the PT tide gauge). So that gives a sense of what a 11.5′ water level (tide prediction plus surge) on the storm surge tool would look like (which has only been seen twice in the last 50 years, most recently on 12/27/22). (Note that these use only the elevation of a given site, and any physical barriers like sea walls, etc., are not taken into account.)
- You can learn more about this project at this website, which also provides instructions for accessing the database of all king tides monitored by the team.
- If you would like more information, contact the Local 20/20 climate group at CAG@L2020.org.
