Kawaihae Breakwater Surf Stats

This chart describes the variation of swells directed at Kawaihae Breakwater through an average July. It is based on 3720 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the best grid node based on what we know about Kawaihae Breakwater. In the case of Kawaihae Breakwater, the best grid node is 18 km away (11 miles). The rose diagram describes the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These occurred only 66% of the time. Green and yellow show increasing swell sizes and red represents the highest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell occurs. The diagram implies that the most common swell direction, shown by the longest spokes, was SW, whereas the the dominant wind blows from the NNE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Kawaihae Breakwater and away from the coast. We lump these in with the no surf category of the bar chart. To keep it simple we don't show these in the rose diagram. Because wind determines whether or not waves are good for surfing at Kawaihae Breakwater, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical July, swells large enough to cause clean enough to surf waves at Kawaihae Breakwater run for about 1.0% of the time.

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