Napier - Marine Parade Swell Statistics, December: All Swell – Any Wind
This image illustrates the combination of swells directed at Napier - Marine Parade through an average December and is based upon 2209 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 Napier - Marine Parade, and at Napier - Marine Parade the best grid node is 7 km away (4 miles).
The rose diagram shows the distribution of swell directions and swell sizes, 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 occurred only 59% of the time. Green and yellow represent increasing swell sizes and red shows largest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how frequently that size swell happens.
The diagram suggests that the prevailing swell direction, shown by the largest spokes, was ENE, whereas the the most common wind blows from the NNE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Napier - Marine Parade and away from the coast. We group these 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 surfable at Napier - Marine Parade, 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 December, swells large enough to cause good for surfing waves at Napier - Marine Parade run for about 41% 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.