Airport Lefts Swell Statistics, Fevereiro: Surf with Light or Offshore Winds
This image shows only the swells directed at Airport Lefts that coincided with light winds or offshore conditions through a typical February and is based upon 2102 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 illustrate increasing swell sizes and highest 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 dominant swell direction, shown by the largest spokes, was SW, whereas the the dominant wind blows from the W. 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 40% of the time, equivalent to 11 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal February but 22% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 22%, equivalent to (6 days). Taking into account the proportion of these swells that coincided with forecast offshore winds, and given the fact that Airport Lefts is exposed to open water swells, we calculate that clean surf can be found at Airport Lefts about 40% of the time and that surf is messed up by onshore wind 60% of the time. This is means that we expect 28 days with waves in a typical February, of which 11 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.