Anse Couleuvre Swell Statistics, July: All Swell – Any Wind
The graph shows the combination of swells directed at Anse Couleuvre through a typical July, based on 2480 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the best grid node based on what we know about Anse Couleuvre. In this particular case the best grid node is 28 km away (17 miles).
The rose diagram illustrates the distribution of swell directions and swell sizes, 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 occurred only 100% of the time. Green and yellow represent increasing swell sizes and red shows biggest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the most common swell direction, shown by the biggest spokes, was NE, whereas the the prevailing wind blows from the E. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Anse Couleuvre and offshore. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are surfable at Anse Couleuvre, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average July, swells large enough to cause good for surfing waves at Anse Couleuvre run for about 0% 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.