Jetty Surf Stats

This picture illustrates the variation of swells directed at Jetty over a normal May and is based upon 3440 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coast so we have chosen the optimum grid node based on what we know about Jetty. In the case of Jetty, the best grid node is 35 km away (22 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 23% of the time. Green and yellow represent increasing swell sizes and red shows the largest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the dominant swell direction, shown by the longest spokes, was SSE, whereas the the most common wind blows from the SSW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Jetty 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 plot. Because wind determines whether or not waves are clean enough to surf at Jetty, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical May, swells large enough to cause surfable waves at Jetty run for about 77% of the time.

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