Surf forecasting

Surf forecasting is the process of using offshore swell data to predict onshore wave conditions. It is used by millions of people across the world, including professionals who put their forecasts online, meteorologists who work for news crews, and surfers all over the world. It is impossible to make an exact prediction of the surf (shape and size of breaking waves), but by knowing a few factors a good prediction can be made. One needs to have an understanding of how waves are formed, a basic knowledge of bathymetry, and information (such as tides, location, and weather) about the surf spot being forecasted to accurately forecast the surf.

Offshore swells

How waves are made

Waves are created as wind blows over the ocean, transferring its energy into the water. The size of the swell is affected by three variables: the velocity of the wind, its duration, and its fetch, or distance the wind blows over.

Swells

There are two different types of swell that affect the surf conditions: