The Cove at Sandy Hook Swell Statistics, March: All Swell – Any Wind
This picture illustrates the variation of swells directed at The Cove at Sandy Hook through a typical March, based on 2219 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the most applicable grid node based on what we know about The Cove at Sandy Hook. In this particular case the best grid node is 41 km away (25 miles).
The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing 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 occurred only 55% of the time. Green and yellow represent increasing swell sizes and red represents largest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the dominant swell direction, shown by the biggest spokes, was SSE, whereas the the most common 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 The Cove at Sandy Hook and out to sea. We group these 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 clean enough to surf at The Cove at Sandy Hook, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average March, swells large enough to cause surfable waves at The Cove at Sandy Hook run for about 18% 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.