Dinner Plates Swell Statistics, October: All Swell – Any Wind
This chart shows the combination of swells directed at Dinner Plates through an average October. It is based on 1984 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the most applicable grid node based on what we know about Dinner Plates, and at Dinner Plates the best grid node is 36 km away (22 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 show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These occurred only 10% of the time. Green and yellow show increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the most common swell direction, shown by the longest spokes, was SSW, whereas the the prevailing wind blows from the WNW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Dinner Plates and offshore. 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 surfable at Dinner Plates, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical October, swells large enough to cause good for surfing waves at Dinner Plates run for about 90% 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.