Southend Reef Surf Stats

The rose diagram shows the range of swells directed at Southend Reef over a normal June. It is based on 2872 NWW3 model predictions since 2008 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the most applicable grid node based on what we know about Southend Reef, and at Southend Reef the best grid node is 32 km away (20 miles). The rose diagram illustrates the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but without direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These happened only 85% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how commonly that size swell was forecast. The diagram implies that the most common swell direction, shown by the longest spokes, was S, whereas the the prevailing wind blows from the WSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Southend 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 clean enough to surf at Southend Reef, you can view an alternative image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical June, swells large enough to cause surfable waves at Southend Reef run for about 15% of the time.

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