Cape Sebastian Surf Stats

The rose diagram describes the range of swells directed at Cape Sebastian through an average August, based on 3574 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coast so we have chosen the best grid node based on what we know about Cape Sebastian. In the case of Cape Sebastian, the best grid node is 21 km away (13 miles). The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing without direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These were forecast only 12% of the time. Green and yellow represent increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell happens. The diagram indicates that the prevailing swell direction, shown by the biggest spokes, was W, whereas the the dominant wind blows from the N. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Cape Sebastian and out to sea. We group these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at Cape Sebastian, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. In a typical August, swells large enough to cause surfable waves at Cape Sebastian run for about 88% of the time.

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