Ackergill Swell Statistics, October: Surf with Light or Offshore Winds
This image shows only the swells directed at Ackergill that coincided with light winds or offshore conditions through a typical October. It is based on 2480 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 show increasing swell sizes and red shows biggest 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 prevailing swell direction, shown by the longest spokes, was N, whereas the the prevailing 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 9% of the time, equivalent to 3 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal October. Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that Ackergill is exposed to open water swells, we estimate that clean surf can be found at Ackergill about 9% of the time and that surf is spoilt by onshore wind 12% of the time. This is means that we expect 7 days with waves in a typical October, of which 3 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.