This image shows only the swells directed at Thunders that coincided with light winds or offshore conditions through a typical June and is based upon 1594 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 represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the prevailing swell direction, shown by the biggest spokes, was SSW, 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 52% of the time, equivalent to 16 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal June but 16% of the time we expect swell in the range 2-3m (6.5-10ft) 16%, equivalent to (5 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Thunders is exposed to open water swells, we think that that clean surf can be found at Thunders about 52% of the time and that surf is blown out by onshore wind 47% of the time. This is means that we expect 30 days with waves in a typical June, of which 16 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.