Anglet - Les Cavaliers Swell Statistics, September: All Swell – Any Wind
This chart illustrates the combination of swells directed at Anglet - Les Cavaliers over a normal September, based on 2399 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 Anglet - Les Cavaliers. In the case of Anglet - Les Cavaliers, 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 without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These occurred only 15% 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 commonly that size swell was forecast.
The diagram implies that the prevailing swell direction, shown by the largest spokes, was WNW, whereas the the most common wind blows from the N. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Anglet - Les Cavaliers 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 plot. Because wind determines whether or not waves are surfable at Anglet - Les Cavaliers, you can load a different image 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 good for surfing waves at Anglet - Les Cavaliers run for about 85% 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.