Eoropie (Lewis) Swell Statistics, Dicembre: All Swell – Any Wind

This image illustrates the combination of swells directed at Eoropie (Lewis) through a typical December and is based upon 2457 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 best grid node based on what we know about Eoropie (Lewis), and at Eoropie (Lewis) the best grid node is 10 km away (6 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 represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These occurred only 18% of the time. Green and yellow illustrate increasing swell sizes and red shows the largest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell was forecast.

The diagram implies that the prevailing swell direction, shown by the longest spokes, was WNW, whereas the the most common wind blows from the SW. Because the wave model grid is away from the coast, sometimes a strong offshore wind blows largest waves away from Eoropie (Lewis) and out to sea. 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 surfable at Eoropie (Lewis), you can view an alternative image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. Over an average December, swells large enough to cause good for surfing waves at Eoropie (Lewis) run for about 82% 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.