Portrush-East Strand Surf Stats

This picture describes the variation of swells directed at Portrush-East Strand through an average June. It is based on 3506 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind and surf right at the coastline so we have chosen the most applicable grid node based on what we know about Portrush-East Strand, and at Portrush-East Strand the best grid node is 34 km away (21 miles). The rose diagram describes the distribution of swell sizes and directions, 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 occurred 30% of the time. Green and yellow show increasing swell sizes and red represents the highest swells, greater than >3m (>10ft). In either graph, 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 longest spokes, was WNW (which was the same as the dominant wind direction). Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Portrush-East Strand and away from the coast. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are good for surfing at Portrush-East Strand, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical June, swells large enough to cause clean enough to surf waves at Portrush-East Strand run for about 70% of the time.

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