Santa Maria - Anjos Swell Statistics, March: All Swell – Any Wind
The figure illustrates the range of swells directed at Santa Maria - Anjos through an average March and is based upon 2220 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the best grid node based on what we know about Santa Maria - Anjos, and at Santa Maria - Anjos the best grid node is 14 km away (9 miles).
The rose diagram illustrates the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks 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 28% of the time. Green and yellow illustrate increasing swell sizes and red illustrates largest swells greater than >3m (>10ft). In both graphs, 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 longest spokes, was NW, whereas the the most common wind blows from the WSW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Santa Maria - Anjos and away from the coast. We lump these in 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 Santa Maria - Anjos, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. In a typical March, swells large enough to cause surfable waves at Santa Maria - Anjos run for about 72% 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.