Shipwreck Bay-Supertubes Surf Stats

The rose diagram describes the combination of swells directed at Shipwreck Bay-Supertubes through a typical February. It is based on 3120 NWW3 model predictions since 2007 (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 Shipwreck Bay-Supertubes. In this particular case the best grid node is 22 km away (14 miles). The rose diagram illustrates the distribution of swell directions and swell sizes, 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 2% of the time. Green and yellow represent increasing swell sizes and highest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how commonly that size swell happens. The diagram implies that the dominant swell direction, shown by the longest spokes, was SW, whereas the the dominant wind blows from the SE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Shipwreck Bay-Supertubes and away from the coast. We combine these with the no surf category of the bar chart. To keep it simple we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Shipwreck Bay-Supertubes, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average February, swells large enough to cause surfable waves at Shipwreck Bay-Supertubes run for about 34% of the time.

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