Seaford Reef Surf Stats

This picture illustrates the variation of swells directed at Seaford Reef through a typical November. It is based on 3347 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the optimum grid node based on what we know about Seaford Reef, and at Seaford Reef the best grid node is 55 km away (34 miles). The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These happened only 86% 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 was forecast. The diagram suggests that the prevailing swell direction, shown by the longest spokes, was WSW, whereas the the most common wind blows from the S. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Seaford Reef and out to sea. We combine 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 surfable at Seaford Reef, you can view an alternative image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average November, swells large enough to cause good for surfing waves at Seaford Reef run for about 2.0% of the time.

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