Trants Bay/Spleef Reef Surf Stats

This picture shows the range of swells directed at Trants Bay/Spleef Reef through a typical November, based on 3347 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the most applicable grid node based on what we know about Trants Bay/Spleef Reef, and at Trants Bay/Spleef Reef the best grid node is 31 km away (19 miles). The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These happened only 29% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each 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 biggest spokes, was NE, whereas the the prevailing wind blows from the E. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Trants Bay/Spleef Reef 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 plot. Because wind determines whether or not waves are clean enough to surf at Trants Bay/Spleef Reef, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average November, swells large enough to cause surfable waves at Trants Bay/Spleef Reef run for about 71% of the time.

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