Arrifana Swell Statistics, June: Surf with Light or Offshore Winds
This image shows only the swells directed at Arrifana that coincided with light winds or offshore conditions through a typical June. It is based on 2306 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 represent increasing swell sizes and red illustrates the highest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the dominant swell direction, shown by the largest spokes, was NW, whereas the the dominant wind blows from the NW. 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 June but 19% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 19%, equivalent to (6 days). Taking into account the fraction of these swells that coincided with forecast offshore winds, and given the fact that Arrifana is slightly protected from open water swells, we calculate that clean surf can be found at Arrifana about 20% of the time and that surf is messed up by onshore wind 28% of the time. This is means that we expect 14 days with waves in a typical June, 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.