San Juan de Alima Surf Stats

The rose diagram illustrates the range of swells directed at San Juan de Alima over a normal November. It is based on 3347 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the most applicable grid node based on what we know about San Juan de Alima, and at San Juan de Alima the best grid node is 36 km away (22 miles). The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These were forecast only 96% of the time. Green and yellow show increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how often that size swell occurs. The diagram indicates that the most common swell direction, shown by the biggest spokes, was W, whereas the the most common wind blows from the NNW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from San Juan de Alima and out to sea. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at San Juan de Alima, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical November, swells large enough to cause surfable waves at San Juan de Alima run for about 1.0% of the time.

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