Aberavon Swell Statistics, August: 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 August. It is based on 2479 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 illustrate increasing swell sizes and red shows biggest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the dominant swell direction, shown by the longest spokes, was WSW (which was the same as the prevailing 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 8% of the time, equivalent to 2 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal August. Taking into account the fraction of these swells that coincided with forecast offshore winds, and given the fact that Aberavon is exposed to open water swells, we calculate that clean surf can be found at Aberavon about 8% of the time and that surf is messed up by onshore wind 68% of the time. This is means that we expect 24 days with waves in a typical August, of which 2 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.