North Palmetto Point Swell Statistics, August: All Swell – Any Wind
The graph shows the range of swells directed at North Palmetto Point over a normal August, based on 2232 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coast so we have chosen the best grid node based on what we know about North Palmetto Point. In this particular case the best grid node is 22 km away (14 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These happened only 9% of the time. Green and yellow represent increasing swell sizes and red illustrates the biggest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the prevailing swell direction, shown by the longest spokes, was ENE, whereas the the prevailing wind blows from the SE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from North Palmetto Point and offshore. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at North Palmetto Point, you can view an alternative image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical August, swells large enough to cause surfable waves at North Palmetto Point run for about 91% of the time.
IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.