4 Bobs Surf Stats

This chart shows the variation of swells directed at 4 Bobs through a typical February. It is based on 2664 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the best grid node based on what we know about 4 Bobs. In the case of 4 Bobs, the best grid node is 23 km away (14 miles). The rose diagram shows the distribution of swell directions and swell sizes, 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 happened only 0% of the time. Green and yellow show 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 commonly that size swell happens. The diagram implies that the most common swell direction, shown by the biggest spokes, was SSW, whereas the the prevailing wind blows from the WNW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from 4 Bobs and away from the coast. We combine these with the no surf category of the bar chart. To simplify things we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at 4 Bobs, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average February, swells large enough to cause surfable waves at 4 Bobs run for about 21% of the time.

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