Chuns Reef Surf Stats

This picture shows the range of swells directed at Chuns Reef through an average April and is based upon 3360 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the best grid node based on what we know about Chuns Reef. In the case of Chuns Reef, the best grid node is 42 km away (26 miles). The rose diagram illustrates the distribution of swell directions and swell sizes, 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 33% of the time. Green and yellow show increasing swell sizes and red shows the biggest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell occurs. The diagram indicates that the prevailing swell direction, shown by the longest spokes, was NNW, whereas the the prevailing wind blows from the E. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Chuns Reef and away from the coast. We lump these in 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 Chuns Reef, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical April, swells large enough to cause good for surfing waves at Chuns Reef run for about 67% of the time.

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