Jeffs Left Surf Stats

The figure illustrates the variation of swells directed at Jeffs Left through a typical April and is based upon 3360 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 optimum grid node based on what we know about Jeffs Left. In this particular case the best grid node is 28 km away (17 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 illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These were forecast 61% of the time. Green and yellow show increasing swell sizes and red represents largest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the dominant swell direction, shown by the longest spokes, was SW (which was the same as the most common wind direction). Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Jeffs Left and away from the coast. 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 Jeffs Left, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average April, swells large enough to cause surfable waves at Jeffs Left run for about 9% of the time.

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