Assinie Swell Statistics, Spring: Surf with Light or Offshore Winds
This image shows only the swells directed at Assinie that coincided with light winds or offshore conditions over a normal northern hemisphere spring. It is based on 6580 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 red shows largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the prevailing swell direction, shown by the largest spokes, was SSW (which was the same as the most common wind direction). 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 11% of the time, equivalent to 10 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal northern hemisphere spring but 5% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 5%, equivalent to (5 days). Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that Assinie is exposed to open water swells, we estimate that clean surf can be found at Assinie about 11% of the time and that surf is messed up by onshore wind 89% of the time. This is means that we expect 91 days with waves in a typical northern hemisphere spring, of which 10 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.