Blythedale Surf Stats

This picture describes the variation of swells directed at Blythedale through a typical April. It is based on 3360 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 optimum grid node based on what we know about Blythedale. In this particular case the best grid node is 20 km away (12 miles). The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These occurred only 40% of the time. Green and yellow show increasing swell sizes and red represents the highest 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 S, whereas the the dominant wind blows from the E. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Blythedale 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 plot. Because wind determines whether or not waves are good for surfing at Blythedale, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average April, swells large enough to cause clean enough to surf waves at Blythedale run for about 60% of the time.

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