Sunglow Pier Swell Statistics, Winter: All Swell – Any Wind
The rose diagram shows the combination of swells directed at Sunglow Pier over a normal northern hemisphere winter, based on 6365 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the optimum grid node based on what we know about Sunglow Pier. In this particular case the best grid node is 44 km away (27 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These happened 35% of the time. Green and yellow show 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 frequently that size swell occurs.
The diagram suggests that the prevailing swell direction, shown by the largest spokes, was ENE, 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 Sunglow Pier 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 good for surfing at Sunglow Pier, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical northern hemisphere winter, swells large enough to cause clean enough to surf waves at Sunglow Pier run for about 65% 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.