Asilomar Swell Statistics, November: Surf with Light or Offshore Winds
This image shows only the swells directed at Asilomar 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 represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how frequently that size swell was forecast.
The diagram suggests that the dominant swell direction, shown by the biggest spokes, was WNW, whereas the the prevailing wind blows from the N. 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 40% of the time, equivalent to 12 days. Open water swells exceeding >3m (>10ft) only occur 2.0% of the time in a typical November, equivalent to just one day but 19% of the time we expect swell in the range 2-3m (6.5-10ft) 19%, equivalent to (6 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Asilomar is exposed to open water swells, we calculate that clean surf can be found at Asilomar about 40% of the time and that surf is blown out by onshore wind 58% of the time. This is means that we expect 29 days with waves in a typical November, of which 12 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.