Statistiques de Houle pour Anse de Vauville, Automne: Toutes Houles – Tous Vents
The graph illustrates the variation of swells directed at Anse de Vauville through an average northern hemisphere autumn, based on 7248 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 Anse de Vauville. In the case of Anse de Vauville, the best grid node is 19 km away (12 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These occurred 63% of the time. Green and yellow illustrate increasing swell sizes and red represents largest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how frequently that size swell was forecast.
The diagram suggests that the prevailing swell direction, shown by the biggest spokes, was W, whereas the the most common wind blows from the WSW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Anse de Vauville and offshore. We lump these in with the no surf category of the bar chart. To keep it simple we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at Anse de Vauville, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical northern hemisphere autumn, swells large enough to cause surfable waves at Anse de Vauville run for about 37% 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.