Annascaul Rivermouth Swell Statistics, August: Surf with Light or Offshore Winds
This image shows only the swells directed at Annascaul Rivermouth that coincided with light winds or offshore conditions through a typical August and is based upon 2480 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 shows highest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell happens.
The diagram suggests that the most common swell direction, shown by the largest spokes, was WSW, whereas the the dominant wind blows from the W. 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 1.1% of the time, equivalent to 0 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal August but 6% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 6%, equivalent to (2 days). Taking into account the ratio of these swells that coincided with predicted offshore winds, and given the fact that Annascaul Rivermouth is quite sheltered from open water swells, we think that that clean surf can be found at Annascaul Rivermouth about 1.1% of the time and that surf is messed up by onshore wind 31% of the time. This is means that we expect 10 days with waves in a typical August, of which 0 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.