Cliff Beach (Lewis) Swell Statistics, February: All Swell – Any Wind
The rose diagram illustrates the range of swells directed at Cliff Beach (Lewis) through a typical February and is based upon 1808 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 most applicable grid node based on what we know about Cliff Beach (Lewis), and at Cliff Beach (Lewis) the best grid node is 25 km away (16 miles).
The rose diagram shows the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These happened only 15% of the time. Green and yellow represent increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In both graphs, the area of any colour is proportional to how frequently that size swell happens.
The diagram suggests that the dominant swell direction, shown by the biggest spokes, was WNW, whereas the the most common wind blows from the SW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Cliff Beach (Lewis) 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 plot. Because wind determines whether or not waves are surfable at Cliff Beach (Lewis), you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average February, swells large enough to cause good for surfing waves at Cliff Beach (Lewis) run for about 85% 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.