This picture shows the combination of swells directed at Nungas through an average June and is based upon 1594 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 Nungas. In this particular case the best grid node is 27 km away (17 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but 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 0.9% of the time. Green and yellow show increasing swell sizes and red shows the biggest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the dominant swell direction, shown by the largest spokes, was SW, whereas the the prevailing wind blows from the ESE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Nungas 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 surfable at Nungas, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical June, swells large enough to cause good for surfing waves at Nungas run for about 67% 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.