Anse Bertrand Swell Statistics, Autumn: Surf with Light or Offshore Winds
This image shows only the swells directed at Anse Bertrand that coincided with light winds or offshore conditions through a typical northern hemisphere autumn. It is based on 7252 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 illustrates largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the most common swell direction, shown by the largest spokes, was NNE, whereas the the most common wind blows from the E. 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 1.0% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal northern hemisphere autumn but 6% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 6%, equivalent to (5 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Anse Bertrand is quite sheltered from open water swells, we think that that clean surf can be found at Anse Bertrand about 1.0% of the time and that surf is messed up by onshore wind 1.0% of the time. This is means that we expect 2 days with waves in a typical northern hemisphere autumn, of which 1 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.