ADs/Doubles Swell Statistics, March: Surf with Light or Offshore Winds
This image shows only the swells directed at ADs/Doubles that coincided with light winds or offshore conditions over a normal March and is based upon 2220 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 red represents the largest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the most common swell direction, shown by the largest spokes, was E, 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 2.0% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal March. Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that ADs/Doubles is exposed to open water swells, we calculate that clean surf can be found at ADs/Doubles about 2.0% of the time and that surf is blown out by onshore wind 31% of the time. This is means that we expect 10 days with waves in a typical March, of which 1 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.