Shell Island Surf Stats

The rose diagram describes the variation of swells directed at Shell Island over a normal November, based on 3337 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the best grid node based on what we know about Shell Island. In the case of Shell Island, the best grid node is 31 km away (19 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 illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These occurred 70% of the time. Green and yellow show 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 frequently that size swell was forecast. The diagram suggests that the most common swell direction, shown by the longest spokes, was SE, whereas the the dominant wind blows from the NE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Shell Island and offshore. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Shell Island, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical November, swells large enough to cause surfable waves at Shell Island run for about 30% of the time.

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