Arawhata Swell Statistics, All Year: All Swell – Any Wind
The rose diagram illustrates the range of swells directed at Arawhata over a normal year. It is based on 25429 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the most applicable grid node based on what we know about Arawhata. In the case of Arawhata, the best grid node is 27 km away (17 miles).
The rose diagram illustrates the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but 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 only 16% of the time. Green and yellow illustrate increasing swell sizes and red illustrates largest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the prevailing swell direction, shown by the biggest spokes, was WSW, whereas the the most common wind blows from the W. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Arawhata and offshore. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose diagram. Because wind determines whether or not waves are good for surfing at Arawhata, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical year, swells large enough to cause clean enough to surf waves at Arawhata run for about 84% 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.