Statistiques de Houle pour Aberffraw, Novembre: Vagues avec Vents Légers ou Favorables.
This image shows only the swells directed at Aberffraw that coincided with light winds or offshore conditions through a typical November and is based upon 2386 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 represents the biggest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the dominant swell direction, shown by the longest spokes, was SW, whereas the the prevailing wind blows from the WSW. 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 1.9% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal November. Taking into account the proportion of these swells that coincided with expected offshore winds, and given the fact that Aberffraw is exposed to open water swells, we calculate that clean surf can be found at Aberffraw about 1.9% of the time and that surf is spoilt by onshore wind 47% of the time. This is means that we expect 15 days with waves in a typical November, of which 1 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.