Agnes Waters Swell Statistics, August: Surf with Light or Offshore Winds
This image shows only the swells directed at Agnes Waters that coincided with light winds or offshore conditions over a normal August. It is based on 2480 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 illustrate increasing swell sizes and red illustrates biggest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the dominant swell direction, shown by the largest spokes, was ENE, whereas the the prevailing wind blows from the ESE. 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 12% of the time, equivalent to 4 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal August. Taking into account the proportion of these swells that coincided with expected offshore winds, and given the fact that Agnes Waters is exposed to open water swells, we calculate that clean surf can be found at Agnes Waters about 12% of the time and that surf is blown out by onshore wind 37% of the time. This is means that we expect 15 days with waves in a typical August, of which 4 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.