Arinaga Swell Statistics, September: Surf with Light or Offshore Winds
This image shows only the swells directed at Arinaga that coincided with light winds or offshore conditions over a normal September. It is based on 2400 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. Green and yellow illustrate increasing swell sizes and red shows the biggest 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 dominant swell direction, shown by the biggest spokes, was NNW, whereas the the prevailing 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 0.2% of the time, equivalent to 0 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal September. Taking into account the ratio of these swells that coincided with predicted offshore winds, and given the fact that Arinaga is quite sheltered from open water swells, we think that that clean surf can be found at Arinaga about 0.2% of the time and that surf is spoilt by onshore wind 1.8% of the time. This is means that we expect 1 days with waves in a typical September, of which 0 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.