Noosa - Alexandria Bay Swell Statistics, January: All Swell – Any Wind
This image shows the range of swells directed at Noosa - Alexandria Bay over a normal January and is based upon 2372 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the optimum grid node based on what we know about Noosa - Alexandria Bay. In this particular case the best grid node is 40 km away (25 miles).
The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks 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 89% of the time. Green and yellow illustrate increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the prevailing swell direction, shown by the biggest spokes, was SE, whereas the the prevailing wind blows from the E. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Noosa - Alexandria Bay and out to sea. We lump these in with the no surf category of the bar chart. To simplify things we don't show these in the rose diagram. Because wind determines whether or not waves are good for surfing at Noosa - Alexandria Bay, you can select a similar diagram 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 Noosa - Alexandria Bay run for about 11% 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.