Abermawr Swell Statistics, November: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Abermawr that coincided with light winds or offshore conditions over a normal November. It is based on 2387 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 show increasing swell sizes and red shows highest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell happens.
The diagram indicates that the dominant swell direction, shown by the longest spokes, was SW, 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 12% of the time, equivalent to 4 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal November but 6% of the time we expect swell in the range 2-3m (6.5-10ft) 6%, equivalent to (2 days). Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that Abermawr is slightly protected from open water swells, we think that that clean surf can be found at Abermawr about 12% of the time and that surf is spoilt by onshore wind 40% of the time. This is means that we expect 16 days with waves in a typical November, of which 4 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.