Barview Jetty Swell Statistics, December: All Swell – Any Wind
The graph describes the combination of swells directed at Barview Jetty through an average December, based on 1961 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the optimum grid node based on what we know about Barview Jetty, and at Barview Jetty the best grid node is 3 km away (2 miles).
The rose diagram describes 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 15% of the time. Green and yellow illustrate increasing swell sizes and red illustrates the highest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the prevailing swell direction, shown by the largest spokes, was WNW, whereas the the dominant wind blows from the SSE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Barview Jetty and offshore. We combine these with the no surf category of the bar chart. To simplify things we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Barview Jetty, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical December, swells large enough to cause surfable waves at Barview Jetty run for about 85% 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.