Airport Lefts Swell Statistics, February: All Swell – Any Wind
The rose diagram describes the range of swells directed at Airport Lefts through a typical February. It is based on 2102 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 Airport Lefts. In the case of Airport Lefts, the best grid node is 33 km away (21 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast only 0% of the time. Green and yellow represent increasing swell sizes and red represents the highest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the dominant swell direction, shown by the largest spokes, was SW, whereas the the dominant wind blows from the W. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Airport Lefts 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 graph. Because wind determines whether or not waves are good for surfing at Airport Lefts, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average February, swells large enough to cause clean enough to surf waves at Airport Lefts run for about 100% 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.