The Knap Surf Stats

This chart shows the combination of swells directed at The Knap over a normal May. It is based on 3430 NWW3 model predictions since 2007 (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 The Knap, and at The Knap the best grid node is 50 km away (31 miles). The rose diagram illustrates the distribution of swell directions and swell sizes, 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 were forecast 40% of the time. Green and yellow represent increasing swell sizes and red shows biggest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell was forecast. The diagram indicates that the most common swell direction, shown by the largest spokes, was WSW, whereas the the prevailing wind blows from the W. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from The Knap and away from the coast. We combine these 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 The Knap, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical May, swells large enough to cause good for surfing waves at The Knap run for about 0% of the time.

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