A Street Swell Statistics, April: Surf with Light or Offshore Winds
This image shows only the swells directed at A Street that coincided with light winds or offshore conditions through a typical April and is based upon 2160 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 show increasing swell sizes and red illustrates biggest swells greater than >3m (>10ft). 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 SE, whereas the the prevailing wind blows from the SE. 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 0.4% of the time, equivalent to 0 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal April. Taking into account the proportion of these swells that coincided with expected offshore winds, and given the fact that A Street is slightly protected from open water swells, we estimate that clean surf can be found at A Street about 0.4% of the time and that surf is blown out by onshore wind 1.6% of the time. This is means that we expect 1 days with waves in a typical April, of which 0 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.