Aberaeron Swell Statistics, July: All Swell – Any Wind
This image describes the range of swells directed at Aberaeron over a normal July. It is based on 2479 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the coast so we have chosen the best grid node based on what we know about Aberaeron, and at Aberaeron the best grid node is 32 km away (20 miles).
The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These occurred 47% of the time. Green and yellow show increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the most common swell direction, shown by the largest spokes, was WSW (which was the same as the dominant wind direction). Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Aberaeron and offshore. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Aberaeron, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical July, swells large enough to cause surfable waves at Aberaeron run for about 11% of the time.
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.