Freeport Channel Swell Statistics, April: All Swell – Any Wind
The graph shows the combination of swells directed at Freeport Channel through an average April and is based upon 1680 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 Freeport Channel. In this particular case the best grid node is 42 km away (26 miles).
The rose diagram shows the distribution of swell directions and swell sizes, 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 only 43% of the time. Green and yellow illustrate increasing swell sizes and red shows the biggest 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 largest spokes, was ESE, whereas the the prevailing 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 Freeport Channel and out to sea. We group these with the no surf category of the bar chart. To keep it simple we don't show these in the rose diagram. Because wind determines whether or not waves are good for surfing at Freeport Channel, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical April, swells large enough to cause clean enough to surf waves at Freeport Channel run for about 1.0% 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.