Posties Surf Stats

This image shows the combination of swells directed at Posties through a typical June. It is based on 3506 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the most applicable grid node based on what we know about Posties, and at Posties the best grid node is 24 km away (15 miles). The rose diagram shows 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 0.5% of the time. Green and yellow illustrate increasing swell sizes and red represents the biggest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the prevailing swell direction, shown by the biggest spokes, was SW, whereas the the prevailing wind blows from the WNW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Posties and out to sea. We group these 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 good for surfing at Posties, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average June, swells large enough to cause clean enough to surf waves at Posties run for about 100% of the time.

read more