Apua Point Swell Statistics, All Year: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Apua Point 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 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 shows the largest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the dominant swell direction, shown by the largest spokes, was SE, whereas the the most common wind blows from the ENE. 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 3% of the time, equivalent to 11 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal year but 1.6% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 1.6%, equivalent to (6 days). Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that Apua Point is exposed to open water swells, we estimate that clean surf can be found at Apua Point about 3% of the time and that surf is spoilt by onshore wind 45% of the time. This is means that we expect 175 days with waves in a typical year, of which 11 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.