Copper Mine Bay Surf Stats

The graph shows the combination of swells directed at Copper Mine Bay through a typical September and is based upon 3360 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the most applicable grid node based on what we know about Copper Mine Bay, and at Copper Mine Bay the best grid node is 10 km away (6 miles). The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These happened only 56% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how often that size swell happens. The diagram indicates that the dominant swell direction, shown by the longest spokes, was ESE (which was the same as the prevailing wind direction). Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Copper Mine Bay and offshore. We lump these in with the no surf category of the bar chart. To keep it simple we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at Copper Mine Bay, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average September, swells large enough to cause surfable waves at Copper Mine Bay run for about 44% of the time.

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