Kahuku Ranch Surf Stats

This chart shows the variation of swells directed at Kahuku Ranch through a typical June and is based upon 3506 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the best grid node based on what we know about Kahuku Ranch, and at Kahuku Ranch the best grid node is 22 km away (14 miles). The rose diagram illustrates the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing 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 happened only 69% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how commonly that size swell was forecast. The diagram implies that the most common swell direction, shown by the longest spokes, was SSW, whereas the the prevailing 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 Kahuku Ranch and out to sea. We lump these in 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 Kahuku Ranch, you can load a different image 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 good for surfing waves at Kahuku Ranch run for about 31% of the time.

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