Caerfai Bay Surf Stats

The graph illustrates the combination of swells directed at Caerfai Bay through a typical July, based on 3720 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the optimum grid node based on what we know about Caerfai Bay. In the case of Caerfai Bay, the best grid node is 22 km away (14 miles). The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast 30% of the time. Green and yellow show increasing swell sizes and red shows largest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell occurs. The diagram implies that the most common swell direction, shown by the largest spokes, was WSW, whereas the the most common wind blows from the W. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Caerfai Bay and away from the coast. We group these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are good for surfing at Caerfai Bay, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average July, swells large enough to cause clean enough to surf waves at Caerfai Bay run for about 27% of the time.

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