Dolphin Point Swell Statistics, July: All Swell – Any Wind
This picture describes the variation of swells directed at Dolphin Point through a typical July and is based upon 2480 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 Dolphin Point. In the case of Dolphin Point, the best grid node is 14 km away (9 miles).
The rose diagram illustrates 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 were forecast only 2% of the time. Green and yellow represent increasing swell sizes and red shows the highest swells, greater than >3m (>10ft). In both graphs, 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 SSW, whereas the the dominant wind blows from the WNW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Dolphin Point and out to sea. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are good for surfing at Dolphin Point, you can load a different image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average July, swells large enough to cause clean enough to surf waves at Dolphin Point run for about 98% 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.