This picture illustrates the variation of swells directed at The Wedge (Allenhurst) through an average January. It is based on 1728 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the most applicable grid node based on what we know about The Wedge (Allenhurst). In the case of The Wedge (Allenhurst), the best grid node is 29 km away (18 miles).
The rose diagram illustrates the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing without direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These happened only 85% of the time. Green and yellow illustrate increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the dominant swell direction, shown by the biggest spokes, was NE, whereas the the most common wind blows from the W. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from The Wedge (Allenhurst) and out to sea. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose plot. Because wind determines whether or not waves are good for surfing at The Wedge (Allenhurst), you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical January, swells large enough to cause clean enough to surf waves at The Wedge (Allenhurst) run for about 15% 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.