Air Guling Swell Statistics, Summer: Surf with Light or Offshore Winds
This image shows only the swells directed at Air Guling that coincided with light winds or offshore conditions through a typical southern hemisphere summer. It is based on 6931 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 either graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the most common swell direction, shown by the longest spokes, was SW, whereas the the dominant wind blows from the W. 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 26% of the time, equivalent to 24 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal southern hemisphere summer but 5% of the time we expect swell in the range 2-3m (6.5-10ft) 5%, equivalent to (5 days). Taking into account the fraction of these swells that coincided with predicted offshore winds, and given the fact that Air Guling is slightly protected from open water swells, we calculate that clean surf can be found at Air Guling about 26% of the time and that surf is messed up by onshore wind 48% of the time. This is means that we expect 67 days with waves in a typical southern hemisphere summer, of which 24 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.