El Porto Beach Swell Statistics, January: All Swell – Any Wind
The graph describes the range of swells directed at El Porto Beach through a typical January and is based upon 2124 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the optimum grid node based on what we know about El Porto Beach, and at El Porto Beach the best grid node is 46 km away (29 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 illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These occurred only 18% of the time. Green and yellow illustrate increasing swell sizes and red illustrates highest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how frequently that size swell was forecast.
The diagram suggests that the dominant swell direction, shown by the longest spokes, was WSW, whereas the the dominant wind blows from the N. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from El Porto Beach and out to sea. We combine these with the no surf category of the bar chart. To simplify things we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at El Porto Beach, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. Over an average January, swells large enough to cause surfable waves at El Porto Beach run for about 82% 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.