Harlech Surf Stats
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- Weather State
- Spot Information
All swells
![](/graphs/statistics/Harlech.surf.statistics.march.gif)
![](/graphs/statistics/SW.animated.gif)
![](/graphs/statistics/SW.label.animated.gif)
This chart shows the variation of swells directed at Harlech through an average March and is based upon 3460 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the optimum grid node based on what we know about Harlech, and at Harlech the best grid node is 46 km away (29 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 illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These happened 44% of the time. Green and yellow illustrate increasing swell sizes and biggest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how frequently that size swell occurs. The diagram suggests that the prevailing swell direction, shown by the biggest spokes, was WSW (which was the same as the prevailing wind direction). Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Harlech and away from the coast. We combine these 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 clean enough to surf at Harlech, you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical March, swells large enough to cause surfable waves at Harlech run for about 27% of the time.