Soulac-sur-Mer Swell Statistics, August: All Swell – Any Wind
This chart illustrates the combination of swells directed at Soulac-sur-Mer through a typical August, based on 1984 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 optimum grid node based on what we know about Soulac-sur-Mer. In the case of Soulac-sur-Mer, the best grid node is 28 km away (17 miles).
The rose diagram shows the distribution of swell sizes and swell direction, 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 6% of the time. Green and yellow represent increasing swell sizes and red shows largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell happens.
The diagram suggests that the most common swell direction, shown by the longest spokes, was WNW, whereas the the most common wind blows from the NW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Soulac-sur-Mer 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 surfable at Soulac-sur-Mer, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average August, swells large enough to cause good for surfing waves at Soulac-sur-Mer run for about 94% 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.