A big influence of the quality of the surf is the tides. Becoming familiar with how the tides may affect your local spots is going to be key to timing your best sessions.
First, let’s cover the basics of what causes the changing tides.
Tide cycles are controlled primarily by the gravitational pull of the moon and secondarily by the gravitational pull of the sun.
As the Earth tilts and rotates around the sun and the moon rotates and goes through it’s phases, the timing and heights of the tides on the coastlines, lakes, and inlets will fluctuate and change.
Geographic and bathymetric factors can have an effect on the conditions of the tides too.
Depending on where you are in the world, you’ll find 3 major types of tide fluctuations:
- Diurnal Tides: one high tide and one low tide each day
- Semidiurnal Tides: two roughly equal high tides and low tides each day
- Mixed Tides: a mix of two different high tides and two different low tides
How Does the Tide Affect the Surf?
There are a few different factors that determine the tide’s influence on the waves:
- Depth of the high or low tide.
- Bathymetry and slop of the seafloor.
- Strength and period of the swell.
Every surf spot is going to react differently to certain tides. You’ll even find the whether the tide is incoming or outgoing will have an influence on the quality of the waves.
Figuring out what works for your favorite spots comes with experience. Some are better on high tides, some low, some outgoing, some incoming, and some are generally unaffected.
The swell or swell combo will determine the tide’s effect too. If the swell has enough power or is coming from the right direction, it may be able to combine with the current tide just right.
While you’ve really got to get to know a certain spot for yourself, here are some general things you might find on certain tides:
- A super high tide can tend to slow waves down and cause them to roll past you.
- A super low tide can tend to drain things out and cause waves to quickly pitch over themselves.
- An incoming tide can sometimes give the surf some push and power, while an outgoing tide may have the opposite effect.
Get to know your spot and you may find yourself with an empty, fun session when everyone else thinks the tides are no good.