The graph describes the combination of swells directed at Ras Al Jazirah through an average year and is based upon 20068 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the most applicable grid node based on what we know about Ras Al Jazirah, and at Ras Al Jazirah the best grid node is 11 km away (7 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 represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These occurred 33% of the time. Green and yellow show increasing swell sizes and red shows the highest 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 prevailing swell direction, shown by the biggest spokes, was SSE, whereas the the dominant wind blows from the S. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Ras Al Jazirah and out to sea. We lump these in 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 Ras Al Jazirah, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. In a typical year, swells large enough to cause good for surfing waves at Ras Al Jazirah run for about 67% 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.