What Does Long Fetch Mean In Sailing?

The term fetch refers to the time and distance covered by the same wind on an unobstructed body of water, which can be considered the momentum zone allowing fetch. This area of ocean or lake surface over which the wind blows in an essentially constant direction generates waves. The stronger the wind and the longer the fetch, the higher the waves become over time.

Waves develop as a result of wind blowing for a certain amount of time (duration) over a certain distance (fetch). The stronger the wind and the longer the fetch, the higher the waves become. The longer the fetch and the greater the wind speed, the more wind energy is transferred to the water surface and the larger the resulting sea state will be.

Fetch length, along with wind speed (wind strength), and duration, determines the size (sea state) of waves produced. If the wind direction is constant, the longer the fetch and the greater the wind speed, the more wind energy is transferred to the water surface and the larger the resulting sea state will be. In an enclosed body of water, fetch is also defined as the distance between the points of minimum and maximum water-surface elevation.

A fetch is a reach with the wind slightly forward of the beam, while a close fetch is a reach. A longer fetch increases the period (interval between wave peaks) of wind-driven waves and swell, creating greater danger in windy conditions. Breaking waves are dangerous when the wave is higher than the fetch, and a steady wind direction creates a long swell from one direction.

Fetch is one of the most important elements with wind that affects us as paddlers, as it is the minimum distance that the wind of a set speed must blow over to build a seaway of a given height and period.