The Jetty Surf Stats

The graph illustrates the variation of swells directed at The Jetty through a typical November, based on 3347 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the best grid node based on what we know about The Jetty. In the case of The Jetty, the best grid node is 40 km away (25 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 occurred only 8% of the time. Green and yellow represent increasing swell sizes and red represents largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the most common swell direction, shown by the longest spokes, was SW, whereas the the most common wind blows from the SSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from The Jetty and out to sea. 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 The Jetty, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average November, swells large enough to cause clean enough to surf waves at The Jetty run for about 92% of the time.

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