St-Jean Surf Stats

The graph shows the range of swells directed at St-Jean through an average April and is based upon 3360 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the optimum grid node based on what we know about St-Jean. In this particular case the best grid node is 20 km away (12 miles). The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast only 42% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how commonly that size swell occurs. The diagram implies that the dominant swell direction, shown by the largest spokes, was NE, whereas the the prevailing wind blows from the E. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from St-Jean and offshore. We lump these in 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 St-Jean, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. In a typical April, swells large enough to cause surfable waves at St-Jean run for about 19% of the time.

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