Armadale Bay Swell Statistics, October: Surf with Light or Offshore Winds
This image shows only the swells directed at Armadale Bay 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 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 biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how frequently that size swell happens.
The diagram suggests that the most common swell direction, shown by the longest 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 41% of the time, equivalent to 13 days. Expect open water swells to exceed >3m (>10ft) 5% of the time (2 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 estimate that clean surf can be found at Armadale Bay about 41% of the time and that surf is spoilt by onshore wind 43% of the time. This is means that we expect 26 days with waves in a typical October, of which 13 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.