Bruny Island - Mabel Bay Surf Stats

The figure shows the variation of swells directed at Bruny Island - Mabel Bay through an average November. It is based on 3347 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the most applicable grid node based on what we know about Bruny Island - Mabel Bay. In the case of Bruny Island - Mabel Bay, the best grid node is 13 km away (8 miles). The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing without direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These were forecast only 9% of the time. Green and yellow show increasing swell sizes and red represents biggest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell was forecast. The diagram implies that the prevailing swell direction, shown by the biggest spokes, was SSW, whereas the the prevailing wind blows from the W. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Bruny Island - Mabel Bay and away from the coast. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose graph. Because wind determines whether or not waves are surfable at Bruny Island - Mabel Bay, you can view an alternative image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. In a typical November, swells large enough to cause good for surfing waves at Bruny Island - Mabel Bay run for about 91% of the time.

read more