Statistiques de Houle pour Augusta Rivermouth, Décembre: Toutes Houles – Tous Vents
This chart illustrates the combination of swells directed at Augusta Rivermouth through a typical December and is based upon 2457 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the most applicable grid node based on what we know about Augusta Rivermouth. In the case of Augusta Rivermouth, the best grid node is 24 km away (15 miles).
The rose diagram shows the distribution of swell sizes and directions, 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 occurred only 65% of the time. Green and yellow show increasing swell sizes and red shows largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the most common swell direction, shown by the biggest spokes, was SSW, whereas the the most common wind blows from the SSE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Augusta Rivermouth and offshore. 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 surfable at Augusta Rivermouth, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average December, swells large enough to cause good for surfing waves at Augusta Rivermouth run for about 35% 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.