Statistiques de Surf de Winthrop Jetty

The graph describes the combination of swells directed at Winthrop Jetty over a normal September and is based upon 3360 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the optimum grid node based on what we know about Winthrop Jetty. In the case of Winthrop Jetty, the best grid node is 41 km away (25 miles). The rose diagram illustrates the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These occurred only 28% of the time. Green and yellow represent increasing swell sizes and red shows the highest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell happens. The diagram implies that the dominant swell direction, shown by the largest spokes, was E, whereas the the dominant wind blows from the SSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Winthrop Jetty and out to sea. We group these with the no surf category of the bar chart. To keep it simple we don't show these in the rose graph. Because wind determines whether or not waves are surfable at Winthrop Jetty, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical September, swells large enough to cause good for surfing waves at Winthrop Jetty run for about 72% of the time.

read more