Ajo Swell Statistics, Spring: Surf with Light or Offshore Winds
This image shows only the swells directed at Ajo that coincided with light winds or offshore conditions through a typical northern hemisphere spring. It is based on 6580 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. Green and yellow illustrate increasing swell sizes and red illustrates largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the dominant swell direction, shown by the largest spokes, was NW (which was the same as the most common wind direction). 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 33% of the time, equivalent to 30 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal northern hemisphere spring 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 ratio of these swells that coincided with forecast offshore winds, and given the fact that Ajo is exposed to open water swells, we think that that clean surf can be found at Ajo about 33% of the time and that surf is messed up by onshore wind 60% of the time. This is means that we expect 85 days with waves in a typical northern hemisphere spring, of which 30 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.