Statistiques de Houle pour Avalon Pier, Avril: Toutes Houles – Tous Vents
The rose diagram illustrates the variation of swells directed at Avalon Pier through an average April. It is based on 2160 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the coast so we have chosen the best grid node based on what we know about Avalon Pier, and at Avalon Pier the best grid node is 17 km away (11 miles).
The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but 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 47% of the time. Green and yellow illustrate increasing swell sizes and red represents the largest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the most common swell direction, shown by the longest spokes, was NE, whereas the the most common wind blows from the W. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Avalon Pier and away from the coast. We combine these 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 Avalon Pier, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical April, swells large enough to cause clean enough to surf waves at Avalon Pier run for about 53% 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.