Aberavon Swell Statistics, July: 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 July. It is based on 2480 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 show increasing swell sizes and highest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how frequently that size swell happens.

The diagram suggests that the prevailing swell direction, shown by the biggest spokes, was W (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 8% of the time, equivalent to 2 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal July. Taking into account the proportion 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 8% of the time and that surf is blown out by onshore wind 63% of the time. This is means that we expect 22 days with waves in a typical July, of which 2 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.