Arguineguin Swell Statistics, May: All Swell – Any Wind
The rose diagram illustrates the range of swells directed at Arguineguin through an average May. It is based on 2200 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the optimum grid node based on what we know about Arguineguin, and at Arguineguin the best grid node is 43 km away (27 miles).
The rose diagram illustrates the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast only 83% of the time. Green and yellow show increasing swell sizes and red illustrates largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the most common swell direction, shown by the longest spokes, was SSW, whereas the the most common wind blows from the N. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Arguineguin and away from the coast. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Arguineguin, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical May, swells large enough to cause surfable waves at Arguineguin run for about 17% 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.