A powerful combination of astronomical forces and a punchy summertime south swell delivered a one-two punch to Southern California beach towns on Monday evening.

In certain coastal communities, the region was walloped by massive “king tides,” pushing water levels to an extreme peak near eight feet in several low-lying areas, sparking street flooding and localized chaos along the coastline.

The coastal inundation was heavily amplified by a small but not insignificant summertime pulse of south swell. A two-to-three-foot swell pushed surf directly on top of the already astronomical high tide. The combination quickly proved overwhelming for vulnerable boardwalks and parking lots. Check out a few chaotic scenes below.

In Oceanside, incoming waves breached the strand, battering parked cars and forcing pedestrians to scramble as rushing whitewater swept across beach-adjacent streets.

Further north in Orange County, the extreme tide the Balboa Peninsula in Newport Beach, where ocean water even temporarily flooded the deck of the iconic Balboa Island Ferry.

So, just as a refresher, what exactly are king tides again?

“King tides” is a popular, non-scientific term used to describe the highest high tides of the year. Formally known as perigean spring tides, they occur when a standard spring tide—the twice-monthly alignment of the sun, moon, and Earth during a new or full moon—coincides perfectly with “perigee,” the precise point in the moon’s monthly orbit when it passes closest to Earth. This alignment maximizes the combined gravitational pull on Earth’s oceans, stretching tides to their absolute calendar extremes.

Related: California’s Monsoon Season: Rain, Heat, Thunderstorms, and a Hurricane Swell On The Way

While king tides occur just a few times a year, this summer’s high-water event serves as a vivid real-world preview of the future. City crews across San Diego and Orange Counties spent the early part of the week operating emergency pumps and deploying sandbags to protect coastal property.

As the extreme tides slowly taper off through Wednesday, residents are left washing corrosive saltwater from boardwalks and assessing the soggy aftermath.

Related: King Tides Pummel Multi-Million Dollar SoCal Beachfront Homes (Video)

This story was originally published by Surfer on Jul 14, 2026, where it first appeared in the News section. Add Surfer as a Preferred Source by clicking here.