Annascaul Rivermouth Swell Statistics, May: 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 May. It is based on 2200 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 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 dominant swell direction, shown by the biggest spokes, was WSW, whereas the the most common 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 1.9% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal May 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 forecast 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 1.9% of the time and that surf is messed up by onshore wind 29% of the time. This is means that we expect 10 days with waves in a typical May, 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.