Jumunjin Surf Stats

The graph describes the range of swells directed at Jumunjin through an average April. It is based on 3359 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the most applicable grid node based on what we know about Jumunjin. In this particular case the best grid node is 20 km away (12 miles). The rose diagram illustrates the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks 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 46% of the time. Green and yellow illustrate increasing swell sizes and highest 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 happens. The diagram implies that the most common swell direction, shown by the longest spokes, was E, whereas the the dominant wind blows from the SW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Jumunjin and offshore. We combine these 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 surfable at Jumunjin, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical April, swells large enough to cause good for surfing waves at Jumunjin run for about 54% of the time.

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