Ardnave Point and Bay (Islay) Swell Statistics, January: Surf with Light or Offshore Winds
This image shows only the swells directed at Ardnave Point and Bay (Islay) that coincided with light winds or offshore conditions through a typical January. It is based on 2372 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. Green and yellow represent increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In both graphs, 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 biggest spokes, was W, whereas the the most common 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 28% of the time, equivalent to 9 days. Expect open water swells to exceed >3m (>10ft) 9% of the time (3 days). Taking into account the fraction of these swells that coincided with forecast offshore winds, and given the fact that Ardnave Point and Bay (Islay) is quite sheltered from open water swells, we calculate that clean surf can be found at Ardnave Point and Bay (Islay) about 28% of the time and that surf is spoilt by onshore wind 35% of the time. This is means that we expect 20 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.