California's coastline got hit hard this month by both powerful atmospheric river storms and "king tides."

What You Need To Know

  • California King Tides arrived on Dec. 23 and 24 and again Jan. 21 and 22

  • Residents and visitors shared countless photos on social media documenting the tides' impacts

  • Volunteer photographers submitted over 1,000 photos to the California King Tides Project

  • The next king tide for California will be in mid-December

For the first half of January, several strong atmospheric river storms generated towering waves that slammed against the coastline.  

Then, king tides rolled in just a week ago, causing flooding and more erosion.  

Imagine if those powerful storms arrived at the same time as king tides.  

King tides refer to both extreme low and extreme high tides.  

Below are two video clips from meteorologist Ferdinand Furer showing, from the exact spot, a king low tide on Jan. 19 and a king high tide the following day.

The California King Tide Project maintains a gallery of many other images thanks to volunteers all across the state who have been documenting king tide impacts with their phone or digital camera.  

“We’ve gotten over a thousand photos so far this season and I expect we may have around 1,500 by the time they all filter in,” said Annie Frankel, who oversees the Public Education Program of the California Coastal Commission.  

Californians are encouraged to upload their recent king tide images to show how their favorite beaches or landmarks are affected.  

Photos serve as a record for future generations

The photos help document current flood risk in coastal areas, visualize the impacts of future sea level rise in a community and serve as a living record of change for future generations, according to the California Coastal Commission.

"One thing that was nice to see this year is that we had a resurgence of local events organized around the king tides, where people can learn together about the issues that are important in their community," said Frankel.   

The Roundhouse Aquarium Teaching Center hosted an event at the Manhattan Beach Pier in partnership with Heal the Bay.

"There was quite a good turnout for an event that took place at about nine in the morning on a Sunday in cold January weather," said Marissa Wu, marine biologist. 

"They learned that one could also visit the local tide pools in the afternoon during the lowest tide of the day to see some of the cool marine creatures that normally hang out under the water out of sight," said Wu.

Balboa Island, Newport Beach (Courtesy: @ca_king_tides on Instagram)

The cause of "king tides"

King tides occur due to the extra pull from a new moon during morning tides.

"I personally have noticed that having these tides after our recent storms are changing beach topography," said Claire Arre, Marine Restoration Director at Orange County Coastkeeper. 

"We had sand erosion from freshwater runoff, but then the king tides brought that sand back in for some places and deposited it in places not familiar to us. We have mountains of sand in some parking lots next to beaches with limited sand. It is a strange sight to see in such a short period of time," added Arre.

The purpose of documenting king tides is to give the world a glimpse of the future so city leaders can take action before it's too late.  

"I just hope that this inspires people to make changes in their own lives, as well as how they vote and how they plan their futures," added Arre.  

Our team of meteorologists dives deep into the science of weather and breaks down timely weather data and information. To view more weather and climate stories, check out our weather blogs section.