Types of Tides Explained: Spring, Neap, King and Minus Tides

The ocean at a Southern California beach never sits still. Twice a day it climbs the sand and twice a day it pulls back, and the size and timing of those swings change all month. Knowing the types of tides, and what each one does to the surf zone, is one of the simplest ways to make a beach day safer. Here's what causes tides, how spring, neap, king and minus tides work, and how to read a tide chart like a lifeguard.

What causes tides?

Tides are driven mostly by the moon. Its gravity, working with the motion of the Earth and moon around each other, raises two bulges of water on opposite sides of the planet. As the Earth spins, your beach rotates into and out of those bulges, and you see that as high and low tide.

The sun plays a supporting role. NOAA notes the sun is about 27 million times more massive than the moon but roughly 390 times farther away, so its tide-generating force is only about half of the moon's.

Timing follows the moon too. A lunar day lasts 24 hours and 50 minutes, so high tides come about 12 hours and 25 minutes apart and arrive roughly 50 minutes later each day. If low tide was at noon yesterday, it won't be at noon today.

What are the three types of tides?

Continents block the tide from flowing freely around the globe, so coastlines end up with different daily rhythms. NOAA sorts them into three types of tides.

Diurnal tides

One high tide and one low tide each lunar day. The Gulf of Mexico is the main U.S. example.

Semidiurnal tides

Two highs and two lows each day, of roughly equal height. This pattern is typical of the U.S. East Coast.

Mixed semidiurnal tides

Two highs and two lows each day, but of unequal height. This is the West Coast pattern, from Ventura County to San Clemente. NOAA classifies its Santa Monica tide station as a mixed tide station.

On a mixed coast, every day has a higher high, a lower high, a higher low and a lower low. In practice, you get one big swing and one gentler swing each day. The chart below shows a sample 24 hours on a Southern California beach.

The lower low uncovers tide pools and changes how waves break over sandbars. The higher high pushes water up to the rocks and bluffs.

Spring tide vs neap tide: what's the difference?

Twice a month, around the new moon and the full moon, the Earth, sun and moon line up. The sun's pull adds to the moon's, so high tides run a little higher and low tides a little lower than average. These are spring tides. The name has nothing to do with the season. It comes from the tide "springing forth," and spring tides happen all year.

About seven days later, at the first and third quarter moons, the sun and moon sit at right angles to the Earth. The sun's pull partly cancels the moon's, which gives you neap tides: lower highs, higher lows and a smaller daily range.

Here is what that looks like in NOAA's predictions for the Santa Monica station, one week apart in December 2026, in feet above mean lower low water.

Same beach, same month, three times the swing. Tides also run larger when the moon is near perigee, its closest point to Earth, and NOAA notes that ranges strengthen around early January, when the Earth is closest to the sun. That helps explain why this season's California king tide dates all fall between late November and January.

What is a king tide?

"King tide" is not a scientific term. NOAA describes it as a popular name for exceptionally high tides, which typically arrive around a new or full moon when the moon is also near perigee. Think of it as a spring tide with extra muscle.

The California Coastal Commission's King Tides Project invites the public to photograph the shoreline during the highest predicted tides of the year, previewing how today's rare high water could become normal as sea levels rise. Statewide dates for the 2026-27 season:

• November 24-26, 2026
• December 23-25, 2026
• January 21-22, 2027

This season deserves extra respect. Scripps Institution of Oceanography notes that two long tidal cycles, the 18.6-year lunar nodal cycle and the 4.4-year lunar perigee cycle, are near their peaks in 2026, setting up strong king tides around Christmas on top of sea levels already lifted by El Niño. The Coastal Commission warns that actual water levels can exceed predictions. Our guide to El Niño and the Southern California ocean explains why.

What is a minus tide?

U.S. tide heights are measured from a baseline called mean lower low water, or MLLW. NOAA defines it as the average of each day's lower low tide over the 1983-2001 national tidal datum epoch, and it is the zero line for official predictions. A minus tide, or negative tide, is a low tide that drops below that average. A prediction of -1.9 ft means the water should sit 1.9 feet below a typical daily low.

Minus tides travel with king tides. The Coastal Commission points out that king tide days also bring extreme low tides, some of the best tide pooling of the year. At Cabrillo National Monument in San Diego, the National Park Service says convenient daylight low tides are most common in winter around full and new moons. NOAA's Santa Monica predictions fit that pattern, with a -1.9 ft low at 3:56 p.m. on December 24, 2026.

Where to tide pool in Southern California

• Leo Carrillo State Park, Malibu: California State Parks highlights its reefs, tide pools and coastal caves. See our Malibu service area.
• Point Dume, Malibu: Volcanic rock forms shallow tide pools along the Point Dume State Marine Reserve, where taking marine life is prohibited.
• Abalone Cove, Rancho Palos Verdes: A state marine conservation area protects quiet tide pools on the Palos Verdes shoreline, a short drive from the South Bay.
• Crystal Cove State Park, between Newport Beach and Laguna Beach: State Parks lists tide pools among the park's draws. See our Orange County coverage.

Most of these spots are marine protected areas, so look and don't collect. The Coastal Commission's advice: step only on bare rock or sand, and leave everything as you found it.

How do tides affect swimming and surf?

Tides change where and how waves break, and that changes the hazards in the water.

Rip currents and low tide

Rip currents are not tides, but the tide affects them. According to the National Weather Service, on beaches with a tide range of less than 6 feet, rip currents often flow faster about an hour or two on either side of low tide, when shallower water makes waves break harder over sandbars. Around high tide, deeper water can weaken rips or shut some down. Santa Monica's average daily range is about 5.4 feet, so that rule of thumb fits many local sandbar beaches.

The NWS adds that channel rips typically move 1 to 2 feet per second and can reach 8 feet per second. Rips have not been found to be stronger on an outgoing tide than an incoming one, so the water level matters, not the direction. Learn how to spot and escape them in our rip current guide.

Shorebreak and higher water

Shorebreak is a wave that dumps directly onto a steep beach. The NWS lists trauma injuries, notably to the neck, as its main hazard. A 2019 study of lifeguard-recorded surf zone injuries in southwest France found shorebreak injuries clustered around higher water levels, when waves broke on the steepest part of the beach. A rising tide can move the break right onto the sand where people wade.

Getting cut off by the tide

A rocky point you can stroll around at low tide can become a wave-washed dead end a few hours later. The Coastal Commission's advice for tide poolers is direct: don't let a wave or the incoming tide surprise you. Before you round any point or enter a pocket cove, check when the tide turns and plan to be back well before then.

Low tide has its own trap: NOAA notes that large waves can crash over shallow sandbars and hidden rocks. Never dive headfirst into the surf.

How to read a tide chart

A tide chart lists the predicted times and heights of each high and low tide. NOAA Tides and Currents publishes free official predictions, and the Santa Monica station (ID 9410840) is a handy reference for the Westside and Malibu. Here is NOAA's prediction for Santa Monica on December 24, 2026.

1. Pick the closest station. Tide timing and height shift along the coast.
2. Check the datum. Heights are in feet above MLLW. Zero is an average lower low, and a negative number is a minus tide.
3. Check the time zone. NOAA can display standard or daylight time, so confirm which one you are reading.
4. Spot the mixed pattern. This day has a big high (7.3 ft), a small high (3.9 ft), a modest low (2.1 ft) and a deep minus low (-1.9 ft).
5. Compare to normal. Santa Monica's mean higher high water is about 5.4 ft, so 7.3 ft is nearly 2 feet above a typical higher high. Expect water much farther up the beach than usual that morning.
6. Remember it's a prediction. Tide tables are based on astronomy. Storms, surf and El Niño can push real water levels higher.

Read it like a lifeguard: this day brings the narrowest beach in the morning and open tide pools in the afternoon. If there is swell, rips on sandbar beaches will likely pull hardest from about 2 to 6 p.m. Pair the chart with a surf forecast and our guide to reading ocean conditions.

Tide safety tips for beachgoers

• Check before you go. NOAA recommends arriving informed about local weather, surf and tide forecasts.
• Swim near a lifeguard. For a private beach party or family event, book a private lifeguard to keep eyes on the water.
• Around low tide on sandbar beaches, expect stronger rip currents, especially with swell.
• Around high tide on steep beaches, watch for shorebreak and keep kids back from the waterline.
• Set a turnaround time before tide pooling or walking around points.
• Stay off jetties and wave-washed rocks on king tide days and in big surf.
• Never turn your back on the ocean.

Tides are one of the few ocean hazards you can predict months ahead, so a few minutes with a tide chart goes a long way. Planning a group day on the sand? Check our service areas and pricing.