Hole-in-the-Wall Swell Statistics, September: All Swell – Any Wind
This picture shows the variation of swells directed at Hole-in-the-Wall through a typical September and is based upon 2160 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coast so we have chosen the best grid node based on what we know about Hole-in-the-Wall. In this particular case the best grid node is 38 km away (24 miles).
The rose diagram describes the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These occurred only 26% of the time. Green and yellow represent increasing swell sizes and red shows the biggest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the prevailing swell direction, shown by the longest spokes, was S, whereas the the prevailing wind blows from the SE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Hole-in-the-Wall and away from the coast. We group these with the no surf category of the bar chart. To keep it simple we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Hole-in-the-Wall, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average September, swells large enough to cause surfable waves at Hole-in-the-Wall run for about 74% 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.