Ribeira da Janela Surf Stats

This chart illustrates the combination of swells directed at Ribeira da Janela over a normal August. It is based on 3590 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 Ribeira da Janela. In this particular case the best grid node is 22 km away (14 miles). The rose diagram describes the distribution of swell sizes and directions, 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 occurred only 11% of the time. Green and yellow show increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how often that size swell happens. The diagram indicates that the dominant swell direction, shown by the biggest spokes, was NNW, whereas the the most common wind blows from the NNE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Ribeira da Janela and offshore. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are surfable at Ribeira da Janela, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical August, swells large enough to cause good for surfing waves at Ribeira da Janela run for about 89% of the time.

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