Bambra Reef Swell Statistics, Summer: All Swell – Any Wind
The figure describes the range of swells directed at Bambra Reef over a normal southern hemisphere summer, based on 6365 NWW3 model predictions since 2006 (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 Bambra Reef, and at Bambra Reef the best grid node is 67 km away (42 miles).
The rose diagram illustrates 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 happened only 31% of the time. Green and yellow show increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In each 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 largest spokes, was SSW, whereas the the dominant wind blows from the WNW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Bambra Reef and out to sea. We lump these in with the no surf category of the bar chart. To keep it simple we don't show these in the rose plot. Because wind determines whether or not waves are surfable at Bambra Reef, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical southern hemisphere summer, swells large enough to cause good for surfing waves at Bambra Reef run for about 27% 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.