Armadale Bay Swell Statistics, All Year: Surf with Light or Offshore Winds
This image shows only the swells directed at Armadale Bay that coincided with light winds or offshore conditions over a normal year. It is based on 28044 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 shows biggest 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 dominant swell direction, shown by the largest spokes, was WNW, 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 39% of the time, equivalent to 142 days. Expect open water swells to exceed >3m (>10ft) 5% of the time (18 days). Taking into account the fraction of these swells that coincided with forecast offshore winds, and given the fact that Armadale Bay is exposed to open water swells, we calculate that clean surf can be found at Armadale Bay about 39% of the time and that surf is messed up by onshore wind 46% of the time. This is means that we expect 310 days with waves in a typical year, of which 142 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.