Over 20,000 wetsuits & accessories in stock today!

Secure Checkout

How to Read Swell Charts

   April 11th, 2022   Posted In: How-To  

How to Read Swell Charts

The ability on how to read swell charts is essential to locating high-quality waves. Surfers used weather forecasts and tide maps to predict the waves before the Internet. Most of the time, finding a wave required driving to the ocean with a surfboard strapped to your car. You surfed if there were waves and went for a paddle if the water was calm, or stayed home. 

Checking a surf forecast online provides surfers with a wealth of information, including wave heights and periods, swell directions and wind directions, and the tides. A surf forecast can help to determine how big the waves will be the next day. When knowing how to read a swell chart, here are the key factors to have in mind.

Swell Height

The swell height is the result when an offshore buoy measures the distance from the wave’s trough to its peak. The average height of unbroken waves flowing over a buoy is what you’ll see on a surf report.

Swell Direction

Knowing where the wave is coming from can help you predict how the waves will reach your surf spot.

Swell Period

This term refers to the time it takes for waves to pass the same fixed location several times over. A thorough understanding of the swell phase is essential for surfers since it determines the quality of their next session.

In general, short-period waves are caused by a nearby storm that has not yet gained enough speed and strength. For instance, if a surf report reads 2 feet at 5 seconds (period). It means tiny, weak waves which make surfing harder. The quicker and more powerful the waves will be, the longer the swell period lasts.

Here’s a table of Surf Quality based on Swell Period

Wind Direction

The best conditions for surfing would be if there was no wind at all. Glassy waves would be the result under these circumstances, which is a surfer’s dream. Regardless, even with a little wind, the weather may still be great. Surfing is primarily affected by two types of wind conditions: onshore and offshore wind.

Onshore Wind

This sort of wind is unfavorable for surfing because it creates a lot of chop on the wave’s surface, which makes it more difficult to ride. As the surge is broken up by offshore breezes, the wave height is reduced. A small amount of onshore wind, however, might be welcomed by surfers who enjoy doing aerial techniques, as it keeps their surfboards fastened to their feet when in the air.

Offshore Wind

Offshore winds smoother waves, which blow from the land toward the sea and into the incoming waves, holding them up until they break. The barrel form that every surfer dreams of is made possible by offshore breezes grooming the wave. Offshore winds, on the other hand, can be an issue. To make matters worse, if the wind is blowing too strong, surfers trying to take off on a wave may find themselves pushed back or sprayed with a mist of water from the cresting wave.


It is essential to know how tides affect waves at a specific surfing location. The ocean floor, which is required for a wave to break, is exposed or hidden depending on the tide. High tide is preferable for some areas, while low to mid tide is better for others. It might take some time to figure out which tide is optimal for your surfing location.

Because sand bars may be too thin or exposed at low tide, forcing the wave to shut off or break all at once, most beach breakers perform best at mid-to-high tides. Low to mid-tide is the greatest time to take advantage of reef breaks since the higher tides cause the waves to slow down or flatten out. A wave must have a shallow bottom to create friction and force the wave to stand up and break on itself. However, because of exposed spiky coral or rocks, some reef breaks are extremely shallow and unsafe to surf at very low tides.

The moon controls the tides, hence they can be predicted with a high degree of accuracy. Every day, most coastal locations experience two high tides and two low tides. Surf forecasts can tell you when and how high and low the tides will be on any given day. The range of high and low tides will also alter depending on the moon’s phase. There will be a dramatic shift in the range of tides on a full moon, which will be followed by a dramatic shift in the range on a new moon.

Quadri Abdur is an enthusiastic writer who creates well-researched, SEO articles and website content for websites, blogs, and social media. His other interests include watching football, rom-com & high school drama TV shows, playing games, and researching new technologies.

Latest Posts by Quadri Abdur (see all)

Leave a Reply

Your email address will not be published. Required fields are marked *