Apollo Bay Swell Statistics, January: All Swell – Any Wind
The figure shows the variation of swells directed at Apollo Bay over a normal January. It is based on 2372 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coast so we have chosen the optimum grid node based on what we know about Apollo Bay. In this particular case the best grid node is 31 km away (19 miles).
The rose diagram shows the distribution of swell sizes and swell direction, 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 happened only 3% of the time. Green and yellow illustrate increasing swell sizes and red represents the biggest 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 largest spokes, was SW, whereas the the prevailing wind blows from the S. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Apollo Bay and offshore. We lump these in with the no surf category of the bar chart. To keep it simple we don't show these in the rose graph. Because wind determines whether or not waves are good for surfing at Apollo Bay, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical January, swells large enough to cause clean enough to surf waves at Apollo Bay run for about 95% 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.