The figure shows the range of swells directed at Canal through a typical southern hemisphere autumn. It is based on 5138 NWW3 model predictions since 2007 (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 Canal, and at Canal the best grid node is 7 km away (4 miles).
The rose diagram describes the distribution of swell sizes and directions, 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 71% of the time. Green and yellow illustrate increasing swell sizes and red represents the biggest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell happens.
The diagram indicates that the most common swell direction, shown by the largest spokes, was ESE, whereas the the prevailing wind blows from the NE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Canal and away from the coast. We group these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at Canal, 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 southern hemisphere autumn, swells large enough to cause surfable waves at Canal run for about 29% of the time.
IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.