San Miguel - Areias Swell Statistics, Novembro: Surf with Light or Offshore Winds
This image shows only the swells directed at San Miguel - Areias that coincided with light winds or offshore conditions through a typical November and is based upon 2387 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. Green and yellow illustrate increasing swell sizes and red shows largest swells greater than >3m (>10ft). 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. The chart at the bottom shows the same thing but without direction information. For example, swells larger than 1.5 feet (0.5m) coincided with good wind conditions 22% of the time, equivalent to 7 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal November but 9% of the time we expect swell in the range 2-3m (6.5-10ft) 9%, equivalent to (3 days). Taking into account the proportion of these swells that coincided with predicted offshore winds, and given the fact that San Miguel - Areias is slightly protected from open water swells, we estimate that clean surf can be found at San Miguel - Areias about 22% of the time and that surf is spoilt by onshore wind 51% of the time. This is means that we expect 22 days with waves in a typical November, of which 7 days should be clean enough to surf.
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.