Gills Bay Surf Stats

This picture describes the range of swells directed at Gills Bay through a typical October. It is based on 3471 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 most applicable grid node based on what we know about Gills Bay. In this particular case the best grid node is 45 km away (28 miles). The rose diagram describes 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 occurred only 12% of the time. Green and yellow show increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In both graphs, 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 biggest spokes, was NW, whereas the the dominant wind blows from the SW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Gills Bay 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 Gills Bay, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average October, swells large enough to cause surfable waves at Gills Bay run for about 75% of the time.

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