San Miguel - Areias Swell Statistics, November: All Swell – Any Wind
The rose diagram illustrates the combination of swells directed at San Miguel - Areias over a normal November. It is based on 2387 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the optimum grid node based on what we know about San Miguel - Areias. In the case of San Miguel - Areias, the best grid node is 21 km away (13 miles).
The rose diagram shows the distribution of swell sizes and directions, while the graph at the bottom shows the same thing without 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 26% of the time. Green and yellow represent 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 frequently that size swell occurs.
The diagram suggests that the most common 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 San Miguel - Areias 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 San Miguel - Areias, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical November, swells large enough to cause good for surfing waves at San Miguel - Areias run for about 73% 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.