Calafia Swell Statistics, Winter: All Swell – Any Wind

The graph describes the variation of swells directed at Calafia over a normal northern hemisphere winter and is based upon 6931 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the best grid node based on what we know about Calafia, and at Calafia the best grid node is 30 km away (19 miles).

The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but without direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These occurred only 95% of the time. Green and yellow illustrate increasing swell sizes and highest 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 occurs.

The diagram indicates that the most common swell direction, shown by the largest spokes, was SSW, whereas the the dominant wind blows from the NNW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Calafia and out to sea. We group these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Calafia, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical northern hemisphere winter, swells large enough to cause surfable waves at Calafia run for about 5% 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.