This chart shows the variation of swells directed at Campbells through a typical November. It is based on 1680 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the most applicable grid node based on what we know about Campbells, and at Campbells the best grid node is 36 km away (22 miles).
The rose diagram shows the distribution of swell sizes and directions, while the graph at the bottom shows the same thing without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast only 85% of the time. Green and yellow illustrate increasing swell sizes and red represents the biggest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the most common swell direction, shown by the largest spokes, was SSW, whereas the the prevailing wind blows from the E. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Campbells and offshore. 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 Campbells, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average November, swells large enough to cause surfable waves at Campbells run for about 15% 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.