Momi Bay Surf Stats

The rose diagram shows the range of swells directed at Momi Bay through an average May. It is based on 3414 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the optimum grid node based on what we know about Momi Bay. In this particular case the best grid node is 31 km away (19 miles). The rose diagram illustrates the distribution of swell directions and swell sizes, 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 happened only 5% of the time. Green and yellow represent increasing swell sizes and red illustrates biggest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell happens. The diagram implies that the prevailing swell direction, shown by the biggest spokes, was SSW, whereas the the prevailing wind blows from the ESE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Momi Bay and away from the coast. 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 diagram. Because wind determines whether or not waves are good for surfing at Momi Bay, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical May, swells large enough to cause clean enough to surf waves at Momi Bay run for about 31% of the time.

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