Phillips Pump House Swell Statistics, May: All Swell – Any Wind
This chart describes the variation of swells directed at Phillips Pump House through an average May. It is based on 1910 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the best grid node based on what we know about Phillips Pump House. In the case of Phillips Pump House, the best grid node is 28 km away (17 miles).
The rose diagram illustrates the distribution of swell sizes and swell direction, 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 were forecast 16% of the time. Green and yellow show increasing swell sizes and red represents highest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell happens.
The diagram suggests that the most common swell direction, shown by the biggest spokes, was SE, whereas the the dominant wind blows from the SSW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Phillips Pump House and offshore. We lump these in 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 clean enough to surf at Phillips Pump House, 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 May, swells large enough to cause surfable 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.