Ackergill Swell Statistics, January: Surf with Light or Offshore Winds
This image shows only the swells directed at Ackergill that coincided with light winds or offshore conditions over a normal 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 red illustrates the highest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the prevailing swell direction, shown by the largest spokes, was NNW, whereas the the dominant 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 11% of the time, equivalent to 3 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal January. Taking into account the proportion of these swells that coincided with expected offshore winds, and given the fact that Ackergill is exposed to open water swells, we think that that clean surf can be found at Ackergill about 11% of the time and that surf is blown out by onshore wind 12% of the time. This is means that we expect 7 days with waves in a typical January, of which 3 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.