Atacames Swell Statistics, Winter: Surf with Light or Offshore Winds
This image shows only the swells directed at Atacames that coincided with light winds or offshore conditions over a normal northern hemisphere winter. It is based on 6931 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 illustrate increasing swell sizes and red shows highest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell happens.
The diagram indicates that the most common swell direction, shown by the biggest spokes, was WNW, whereas the the dominant wind blows from the SW. 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 18 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal northern hemisphere winter but 2% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 2%, equivalent to (2 days). Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that Atacames is exposed to open water swells, we estimate that clean surf can be found at Atacames about 20% of the time and that surf is blown out by onshore wind 53% of the time. This is means that we expect 66 days with waves in a typical northern hemisphere winter, of which 18 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.