Playa de San Cibrao Swell Statistics, September: All Swell – Any Wind
This chart illustrates the variation of swells directed at Playa de San Cibrao over a normal September, based on 2160 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 Playa de San Cibrao, and at Playa de San Cibrao the best grid node is 33 km away (21 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 represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These occurred only 18% of the time. Green and yellow show increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In both graphs, 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 biggest spokes, was WNW, whereas the the most common wind blows from the ENE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Playa de San Cibrao and offshore. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are surfable at Playa de San Cibrao, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical September, swells large enough to cause good for surfing waves at Playa de San Cibrao run for about 68% 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.