Rock Point/Pohakuloa Surf Stats

This picture shows the variation of swells directed at Rock Point/Pohakuloa over a normal May. It is based on 3422 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the most applicable grid node based on what we know about Rock Point/Pohakuloa. In the case of Rock Point/Pohakuloa, the best grid node is 30 km away (19 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 only 79% of the time. Green and yellow show increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. 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 largest spokes, was NE, whereas the the prevailing wind blows from the ENE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Rock Point/Pohakuloa and away from the coast. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Rock Point/Pohakuloa, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical May, swells large enough to cause surfable waves at Rock Point/Pohakuloa run for about 21% of the time.

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