Big Lefts Surf Stats

The figure describes the combination of swells directed at Big Lefts over a normal September. It is based on 3360 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the best grid node based on what we know about Big Lefts. In this particular case the best grid node is 36 km away (22 miles). The rose diagram describes 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 occurred only 44% of the time. Green and yellow represent increasing swell sizes and red shows highest 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 prevailing swell direction, shown by the largest spokes, was S, whereas the the dominant wind blows from the ENE. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Big Lefts and out to sea. We group these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose diagram. Because wind determines whether or not waves are surfable at Big Lefts, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical September, swells large enough to cause good for surfing waves at Big Lefts run for about 56% of the time.

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