Phillips Pump House Swell Statistics, May: All Swell – Any Wind
This image illustrates the range of swells directed at Phillips Pump House through an average May. It is based on 1736 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 optimum grid node based on what we know about Phillips Pump House. In this particular case the best grid node is 28 km away (17 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 occurred only 16% of the time. Green and yellow represent increasing swell sizes and red represents the largest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the most common swell direction, shown by the longest spokes, was SE, whereas the the most common wind blows from the SSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Phillips Pump House and out to sea. We lump these in 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 Phillips Pump House, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical May, swells large enough to cause good for surfing waves at Phillips Pump House run for about 84% 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.