Aberavon Swell Statistics, Summer: Surf with Light or Offshore Winds
This image shows only the swells directed at Aberavon that coincided with light winds or offshore conditions through a typical northern hemisphere summer. It is based on 7264 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. Green and yellow represent increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the dominant swell direction, shown by the longest spokes, was WSW (which was the same as the dominant wind direction). 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 9% of the time, equivalent to 8 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal northern hemisphere summer. Taking into account the fraction of these swells that coincided with predicted offshore winds, and given the fact that Aberavon is exposed to open water swells, we think that that clean surf can be found at Aberavon about 9% of the time and that surf is blown out by onshore wind 61% of the time. This is means that we expect 64 days with waves in a typical northern hemisphere summer, of which 8 days should be surfable.
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.