Second Beach (Port St Johns) Surf Stats

This image shows the range of swells directed at Second Beach (Port St Johns) over a normal July. It is based on 3472 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the coastline so we have chosen the best grid node based on what we know about Second Beach (Port St Johns). In the case of Second Beach (Port St Johns), the best grid node is 41 km away (25 miles). The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks 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 55% of the time. Green and yellow illustrate increasing swell sizes and red illustrates biggest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell was forecast. The diagram indicates that the most common swell direction, shown by the longest spokes, was SE, whereas the the prevailing wind blows from the NW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Second Beach (Port St Johns) and away from the coast. 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 Second Beach (Port St Johns), you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical July, swells large enough to cause surfable waves at Second Beach (Port St Johns) run for about 45% of the time.

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