Awatoto Rivermouth Swell Statistics, Settembre: All Swell – Any Wind
The graph illustrates the combination of swells directed at Awatoto Rivermouth through an average September, based on 2400 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the best grid node based on what we know about Awatoto Rivermouth, and at Awatoto Rivermouth the best grid node is 7 km away (4 miles).
The rose diagram shows the distribution of swell sizes and directions, while the graph at the bottom shows the same thing 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 46% of the time. Green and yellow illustrate increasing swell sizes and red illustrates the largest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the most common swell direction, shown by the longest spokes, was ESE, whereas the the most common wind blows from the WNW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Awatoto Rivermouth 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 good for surfing at Awatoto Rivermouth, 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 September, swells large enough to cause clean enough to surf waves at Awatoto Rivermouth run for about 54% 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.