Punta Roquitas Swell Statistics, January: All Swell – Any Wind
The graph illustrates the variation of swells directed at Punta Roquitas over a normal January. It is based on 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 best grid node based on what we know about Punta Roquitas. In the case of Punta Roquitas, the best grid node is 43 km away (27 miles).
The rose diagram illustrates the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but without direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast only 0% of the time. Green and yellow show increasing swell sizes and red represents largest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the most common swell direction, shown by the largest spokes, was SW, whereas the the most common wind blows from the S. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Punta Roquitas and away from the coast. We lump these in with the no surf category of the bar chart. To keep it simple we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Punta Roquitas, you can select a similar diagram that shows only the swells that were predicted to coincide with glassy or offshore wind conditions. During a typical January, swells large enough to cause surfable waves at Punta Roquitas run for about 77% 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.