D and W Surf Stats

The rose diagram describes the variation of swells directed at D and W through a typical May and is based upon 2838 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the optimum grid node based on what we know about D and W. In this particular case the best grid node is 49 km away (30 miles). The rose diagram shows the distribution of swell sizes and swell direction, 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 were forecast only 74% of the time. Green and yellow illustrate increasing swell sizes and red represents 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 largest spokes, was W, whereas the the dominant wind blows from the WSW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from D and W and offshore. We group these with the no surf category of the bar chart. To simplify things we don't show these in the rose diagram. Because wind determines whether or not waves are good for surfing at D and W, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average May, swells large enough to cause clean enough to surf waves at D and W run for about 2.0% of the time.

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