Annascaul Rivermouth Swell Statistics, Summer: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Annascaul Rivermouth that coincided with light winds or offshore conditions over a normal northern hemisphere summer. It is based on 7266 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. Green and yellow represent increasing swell sizes and red shows highest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the most common swell direction, shown by the biggest 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 1.9% of the time, equivalent to 2 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal northern hemisphere summer but 1.9% of the time we expect swell in the range 2-3m (6.5-10ft) 1.9%, equivalent to (2 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Annascaul Rivermouth is quite sheltered from open water swells, we estimate that clean surf can be found at Annascaul Rivermouth about 1.9% of the time and that surf is spoilt by onshore wind 26% of the time. This is means that we expect 25 days with waves in a typical northern hemisphere summer, of which 2 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.