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Gillis ratings
Quality on a good day: 2.0
Consistency of Surf: 3.0
Difficulty Level: 3.0
Crowds: 5.0

Overall: 3.6

See all 18 ratings

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Surf Report Feed

Gillis Swell Statistics, May: All Swell – Any Wind

The graph illustrates the variation of swells directed at Gillis through an average May, based on 2838 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind and surf right at the shore so we have chosen the most applicable grid node based on what we know about Gillis. In this particular case the best grid node is 51 km away (32 miles).

The rose diagram describes the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but 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 75% of the time. Green and yellow show 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 commonly that size swell happens.

The diagram implies that the prevailing swell direction, shown by the largest spokes, was WSW, 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 Gillis and out to sea. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Gillis, you can load a different image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. In a typical May, swells large enough to cause surfable waves at Gillis run for about 25% 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.