Statistiques de Surf de Porth Dinllaen

The rose diagram illustrates the range of swells directed at Porth Dinllaen through an average August and is based upon 3589 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the coastline so we have chosen the best grid node based on what we know about Porth Dinllaen, and at Porth Dinllaen the best grid node is 8 km away (5 miles). The rose diagram describes the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing without 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 49% of the time. Green and yellow show increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In either graph, the area of any colour is proportional to how often that size swell happens. The diagram indicates that the most common swell direction, shown by the longest spokes, was SW, whereas the the most common wind blows from the WSW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Porth Dinllaen and out to sea. We group these with the no surf category of the bar chart. To simplify things we don't show these in the rose diagram. Because wind determines whether or not waves are clean enough to surf at Porth Dinllaen, 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 August, swells large enough to cause surfable waves at Porth Dinllaen run for about 1.0% of the time.

read more