uk es it fr pt nl
Surf Break Rating

Rate Usami


Surf Report Feed

Usami Swell Statistics, May: Surf with Light or Offshore Winds

This image shows only the swells directed at Usami that coincided with light winds or offshore conditions over a normal May. It is based on 2838 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how commonly that size swell happens.

The diagram implies that the dominant swell direction, shown by the biggest spokes, was E, whereas the the prevailing wind blows from the SSW. The chart at the bottom shows the same thing but without direction information. For example, swells larger than 1.5 feet (0.5m) coincided with good wind conditions 2.0% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal May. Taking into account the ratio of these swells that coincided with forecast offshore winds, and given the fact that Usami is quite sheltered from open water swells, we think that that clean surf can be found at Usami about 2.0% of the time and that surf is spoilt by onshore wind 0% of the time. This is means that we expect 1 days with waves in a typical May, of which 1 days should be clean enough to surf.

IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.