Estadísticas de Olas para Avalon-North, Otoño: Todo Oleaje – Todo Viento
This picture illustrates the combination of swells directed at Avalon-North through a typical southern hemisphere autumn and is based upon 6580 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 optimum grid node based on what we know about Avalon-North. In the case of Avalon-North, the best grid node is 21 km away (13 miles).
The rose diagram describes the distribution of swell sizes and swell direction, 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 happened only 56% of the time. Green and yellow show increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how often that size swell occurs.
The diagram indicates that the most common swell direction, shown by the biggest spokes, was E, whereas the the most common wind blows from the SSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Avalon-North and out to sea. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at Avalon-North, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average southern hemisphere autumn, swells large enough to cause surfable waves at Avalon-North run for about 20% 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.