Ajo Swell Statistics, April: 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 April. It is based on 2160 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 illustrate increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the most common swell direction, shown by the biggest spokes, was NW, whereas the the prevailing wind blows from the NNW. 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 10 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal April but 5% of the time we expect swell in the range 2-3m (6.5-10ft) 5%, equivalent to (2 days). Taking into account the fraction of these swells that coincided with predicted offshore winds, and given the fact that Ajo is exposed to open water swells, we estimate that clean surf can be found at Ajo about 33% of the time and that surf is blown out by onshore wind 57% of the time. This is means that we expect 27 days with waves in a typical April, 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.