This image shows only the swells directed at Canal that coincided with light winds or offshore conditions through a typical southern hemisphere spring and is based upon 5144 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 represents 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 ESE, 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 32% of the time, equivalent to 29 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal southern hemisphere spring but 14% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 14%, equivalent to (13 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Canal is exposed to open water swells, we think that that clean surf can be found at Canal about 32% of the time and that surf is messed up by onshore wind 18% of the time. This is means that we expect 46 days with waves in a typical southern hemisphere spring, of which 29 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.