Anawhata Road (Oaonui) Swell Statistics, August: Surf with Light or Offshore Winds
This image shows only the swells directed at Anawhata Road (Oaonui) that coincided with light winds or offshore conditions through a typical August. 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 show increasing swell sizes and red illustrates highest 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 largest spokes, was WSW, whereas the the dominant wind blows from the WNW. 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 25% of the time, equivalent to 8 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal August but 10% of the time we expect swell in the range 2-3m (6.5-10ft) 10%, equivalent to (3 days). Taking into account the ratio of these swells that coincided with forecast offshore winds, and given the fact that Anawhata Road (Oaonui) is exposed to open water swells, we estimate that clean surf can be found at Anawhata Road (Oaonui) about 25% of the time and that surf is blown out by onshore wind 57% of the time. This is means that we expect 25 days with waves in a typical August, of which 8 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.