This image shows only the swells directed at Devil s Punch Beverly Beach that coincided with light winds or offshore conditions over a normal November and is based upon 1680 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 show 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 often that size swell was forecast.
The diagram indicates that the dominant swell direction, shown by the longest spokes, was WNW, whereas the the prevailing wind blows from the SSW. 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 26% of the time, equivalent to 8 days. Expect open water swells to exceed >3m (>10ft) 8% of the time (2 days). Taking into account the proportion of these swells that coincided with forecast offshore winds we estimate that clean surf can be found at Devil s Punch Beverly Beach about 26% of the time and that surf is messed up by onshore wind 71% of the time. This is means that we expect 29 days with waves in a typical November, of which 8 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.