Port Denison Surf Stats

The rose diagram describes the variation of swells directed at Port Denison through a typical July, based on 3720 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the coastline so we have chosen the most applicable grid node based on what we know about Port Denison. In the case of Port Denison, the best grid node is 46 km away (29 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 happened only 0.7% of the time. Green and yellow show increasing swell sizes and red represents highest swells greater than >3m (>10ft). In each graph, 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 longest spokes, was SW, whereas the the dominant wind blows from the SSE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Port Denison and offshore. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose graph. Because wind determines whether or not waves are surfable at Port Denison, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average July, swells large enough to cause good for surfing waves at Port Denison run for about 99% of the time.

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