Orakawa Swell Statistics, November: All Swell – Any Wind
The rose diagram shows the range of swells directed at Orakawa over a normal November and is based upon 2147 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 Orakawa, and at Orakawa the best grid node is 43 km away (27 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 illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These were forecast 34% of the time. Green and yellow show increasing swell sizes and red illustrates biggest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the most common swell direction, shown by the largest spokes, was ENE, whereas the the prevailing wind blows from the W. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Orakawa and out to sea. We group these with the no surf category of the bar chart. To simplify things we don't show these in the rose plot. Because wind determines whether or not waves are good for surfing at Orakawa, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical November, swells large enough to cause clean enough to surf waves at Orakawa 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.