King Tides

King Tides, the highest high tides of the year, are fast approaching and we need your help in documenting these high water level events! Please view the tide prediction tables at the project webpage to identify what time and where high tide occurs on May 25-27, June 23-26, and July 21-23. Detailed instructions on how to submit your photos using the free Smartphone App and online database are available at the project webpage and in the attached pdf. We hope to expand our photo survey coverage of more shorelines across all islands – view the project web map to see where we do and do not have photo records.

Documenting high water levels will be especially important this summer in Hawai’i because Hawai’i is experiencing an elevated sea level stand. The elevated water levels are attributed to an unusual combination of ocean eddies with high centers, Pacific-wide climate and sea level variability associated with recent El Niño events and the Pacific Decadal Oscillation, and sea-level rise from human-induced global warming. These unusually high water levels will likely enhance extreme high tides in Hawai’i during the King Tides this May-July. April 28th saw the highest recorded tide level at the Honolulu Harbor tide gauge (outside of a tsunami or storm event), 11 inches (0.9 ft.) above the predicted tide. May, June, and July could possibly exceed that recorded level and have impacts along the coastline, particularly if combined with any swell. 

For the upcoming May King Tide, the University of Hawai‘i Pacific Islands Ocean Observing System’s, PacIOOS, “Shoreline Impact” models forecast both south shore beach flooding from wave run-up and harbor flooding for Hilo, Kawaihae, Kahului, and Honolulu Harbors. 

Help us photograph the coastlines so that we can better understand impacts from King Tides and sea-level rise. 

Questions? Contact,


University of Hawai’i Sea Grant College Program

Center for Coastal and Climate Science and Resilience

Hawai’i and Pacific Islands King Tides Project