This picture illustrates the range of swells directed at Richardsons through a typical November and is based upon 1680 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the best grid node based on what we know about Richardsons. In this particular case the best grid node is 29 km away (18 miles).
The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but 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 were forecast only 30% of the time. Green and yellow illustrate increasing swell sizes and red illustrates largest swells greater than >3m (>10ft). 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 longest spokes, was NE, whereas the the most common wind blows from the E. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Richardsons and away from the coast. 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 clean enough to surf at Richardsons, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average November, swells large enough to cause surfable waves at Richardsons run for about 70% 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.