Hole-in-the-Wall Swell Statistics, September: All Swell – Any Wind
This image shows the variation of swells directed at Hole-in-the-Wall over a normal September. It is based on 1920 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 Hole-in-the-Wall. In the case of Hole-in-the-Wall, the best grid node is 38 km away (24 miles).
The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but lacks direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These happened only 25% of the time. Green and yellow illustrate increasing swell sizes and red represents biggest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the most common swell direction, shown by the largest 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 combine 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 Hole-in-the-Wall, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical September, swells large enough to cause clean enough to surf waves at Hole-in-the-Wall run for about 75% 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.