The Strait Surf Stats

This picture shows the variation of swells directed at The Strait through a typical June, based on 3384 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the best grid node based on what we know about The Strait, and at The Strait the best grid node is 44 km away (27 miles). The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These happened only 34% of the time. Green and yellow show increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how commonly that size swell occurs. The diagram implies that the dominant swell direction, shown by the largest spokes, was W, whereas the the prevailing wind blows from the WSW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from The Strait and offshore. We combine these 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 The Strait, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average June, swells large enough to cause surfable waves at The Strait run for about 15% of the time.

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