Aan Golf Statistieken, January: Golven met Licht of Offshore Winden
This image shows only the swells directed at Aan that coincided with light winds or offshore conditions through a typical January and is based upon 2372 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 represents largest swells greater than >3m (>10ft). In each 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 longest spokes, was SW, whereas the the most common wind blows from the W. 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 29% of the time, equivalent to 9 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal January but 9% of the time we expect swell in the range 2-3m (6.5-10ft) 9%, equivalent to (3 days). Taking into account the ratio of these swells that coincided with predicted offshore winds, and given the fact that Aan is slightly protected from open water swells, we calculate that clean surf can be found at Aan about 29% of the time and that surf is blown out by onshore wind 58% of the time. This is means that we expect 27 days with waves in a typical January, of which 9 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.