Garths Reef Surf Stats

This picture shows the range of swells directed at Garths Reef over a normal May, based on 3192 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coast so we have chosen the best grid node based on what we know about Garths Reef, and at Garths Reef the best grid node is 33 km away (21 miles). The rose diagram describes the distribution of swell sizes and directions, 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 occurred only 20% of the time. Green and yellow represent increasing swell sizes and red illustrates the biggest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the most common swell direction, shown by the longest spokes, was WNW, whereas the the prevailing wind blows from the NW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Garths Reef and out to sea. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Garths Reef, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical May, swells large enough to cause surfable waves at Garths Reef run for about 39% of the time.

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