The rose diagram shows only the swells directed at Sandend Bay that coincided with light winds or offshore conditions over a normal June. It is based on 1594 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 red shows 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 most common swell direction, shown by the largest spokes, was NNE, whereas the the prevailing wind blows from the NE. 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% of the time, equivalent to 0 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal June. Taking into account the ratio of these swells that coincided with forecast offshore winds, and given the fact that Sandend Bay is slightly protected from open water swells, we calculate that clean surf can be found at Sandend Bay about 0% of the time and that surf is blown out by onshore wind 14% of the time. This is means that we expect 4 days with waves in a typical June, 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.