Arenillas Negras Swell Statistics, October: Surf with Light or Offshore Winds
This image shows only the swells directed at Arenillas Negras that coincided with light winds or offshore conditions through a typical October. It is based on 2480 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 red illustrates largest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell was forecast.
The diagram suggests that the dominant swell direction, shown by the biggest spokes, was SW, whereas the the most common wind blows from the SSW. 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 5% of the time, equivalent to 2 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal October. Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Arenillas Negras is exposed to open water swells, we calculate that clean surf can be found at Arenillas Negras about 5% of the time and that surf is blown out by onshore wind 95% of the time. This is means that we expect 31 days with waves in a typical October, of which 2 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.