Sunglow Pier Swell Statistics, Spring: All Swell – Any Wind
This image illustrates the combination of swells directed at Sunglow Pier over a normal northern hemisphere spring and is based upon 6003 NWW3 model predictions since 2007 (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 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 swell direction, while the graph at the bottom shows the same thing but 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 33% of the time. Green and yellow show increasing swell sizes and red shows the largest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the prevailing swell direction, shown by the largest spokes, was ENE, whereas the the most common wind blows from the SE. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Sunglow Pier and out to sea. We combine these with the no surf category of the bar chart. To keep it simple we don't show these in the rose plot. Because wind determines whether or not waves are surfable at Sunglow Pier, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical northern hemisphere spring, swells large enough to cause good for surfing waves at Sunglow Pier run for about 67% 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.