Santa Maria - Anjos Swell Statistics, March: Surf with Light or Offshore Winds
This image shows only the swells directed at Santa Maria - Anjos that coincided with light winds or offshore conditions over a normal March. It is based on 2220 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. Green and yellow show increasing swell sizes and red shows the 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 WNW, whereas the the most common wind blows from the WSW. 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 20% of the time, equivalent to 6 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal March but 7% of the time we expect swell in the range 2-3m (6.5-10ft) 7%, equivalent to (2 days). Taking into account the proportion of these swells that coincided with forecast offshore winds, and given the fact that Santa Maria - Anjos is exposed to open water swells, we estimate that clean surf can be found at Santa Maria - Anjos about 20% of the time and that surf is spoilt by onshore wind 52% of the time. This is means that we expect 22 days with waves in a typical March, of which 6 days should be surfable.
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.