Anse de Cabestan Swell Statistics, Janeiro: All Swell – Any Wind
The rose diagram shows the range of swells directed at Anse de Cabestan through a typical January, based on 2372 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the most applicable grid node based on what we know about Anse de Cabestan, and at Anse de Cabestan the best grid node is 11 km away (7 miles).
The rose diagram shows the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks 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 happened only 8% of the time. Green and yellow show increasing swell sizes and red illustrates biggest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the prevailing swell direction, shown by the biggest spokes, was WSW (which was the same as the prevailing wind direction). Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Anse de Cabestan and away from the coast. We lump these in 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 clean enough to surf at Anse de Cabestan, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average January, swells large enough to cause surfable waves at Anse de Cabestan run for about 92% 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.