This image shows only the swells directed at Country Club (African Beach) that coincided with light winds or offshore conditions over a normal July. It is based on 1736 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 highest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how frequently that size swell was forecast.
The diagram suggests that the most common swell direction, shown by the largest spokes, was SE, whereas the the dominant wind blows from the NW. 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 32% of the time, equivalent to 10 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal July but 7% of the time we expect swell in the range 2-3m (6.5-10ft) 7%, equivalent to (2 days). Taking into account the fraction of these swells that coincided with predicted offshore winds, and given the fact that Country Club (African Beach) is exposed to open water swells, we estimate that clean surf can be found at Country Club (African Beach) about 32% of the time and that surf is messed up by onshore wind 46% of the time. This is means that we expect 24 days with waves in a typical July, of which 10 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.