Barranca Surf Stats
All swells



The figure describes the variation of swells directed at Barranca over a normal April. It is based on 3360 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coastline so we have chosen the optimum grid node based on what we know about Barranca. In this particular case the best grid node is 17 km away (11 miles). The rose diagram illustrates the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing 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 6% of the time. Green and yellow show increasing swell sizes and highest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how commonly that size swell was forecast. The diagram implies that the most common swell direction, shown by the biggest spokes, was ESE, whereas the the dominant wind blows from the E. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Barranca and offshore. 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 plot. Because wind determines whether or not waves are clean enough to surf at Barranca, you can select a similar diagram that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical April, swells large enough to cause surfable waves at Barranca run for about 94% of the time.
Kudos to everyone who helped us debug this over the past 3 months.
Be sure to click on the Advanced Surf option to see extra details about the sea-state. Look out for crossing swells and short period local wind swells and chop that will often spoil a groundswell even if the wind is perfect. As yet there is no allowance for this in the swell rating. This is something we are working on.