Anse des Lezards Swell Statistics, Spring: All Swell – Any Wind
The graph describes the range of swells directed at Anse des Lezards through a typical northern hemisphere spring and is based upon 6580 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coast so we have chosen the best grid node based on what we know about Anse des Lezards, and at Anse des Lezards the best grid node is 18 km away (11 miles).
The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These occurred only 32% of the time. Green and yellow represent increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the prevailing swell direction, shown by the biggest spokes, was NE, whereas the the dominant wind blows from the E. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Anse des Lezards and away from the coast. We group these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Anse des Lezards, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average northern hemisphere spring, swells large enough to cause surfable waves at Anse des Lezards run for about 27% of the time.
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.