Arinaga Swell Statistics, March: All Swell – Any Wind
This image shows the range of swells directed at Arinaga through a typical March, based on 2220 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the optimum grid node based on what we know about Arinaga, and at Arinaga the best grid node is 42 km away (26 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These occurred only 8% of the time. Green and yellow represent increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the most common swell direction, shown by the longest spokes, was NNW, whereas the the prevailing wind blows from the N. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Arinaga and offshore. 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 Arinaga, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average March, swells large enough to cause surfable waves at Arinaga run for about 24% 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.