Porth Colmon Surf Stats

The graph describes the combination of swells directed at Porth Colmon over a normal October. It is based on 3471 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the most applicable grid node based on what we know about Porth Colmon. In the case of Porth Colmon, the best grid node is 18 km away (11 miles). The rose diagram illustrates the distribution of swell sizes and directions, 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 were forecast 42% of the time. Green and yellow represent increasing swell sizes and red represents the highest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell happens. The diagram suggests that the most common swell direction, shown by the longest spokes, was SW, whereas the the dominant wind blows from the SSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Porth Colmon and out to sea. We combine these with the no surf category of the bar chart. To keep it simple we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Porth Colmon, you can view an alternative image that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical October, swells large enough to cause surfable waves at Porth Colmon run for about 5% of the time.

read more