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Grunters ratings
Quality on a good day: 3.0
Consistency of Surf: 3.0
Difficulty Level: 4.0
Crowds: 3.0

Overall: 3.7

See all 18 ratings

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Surf Report Feed

Grunters Swell Statistics, January: All Swell – Any Wind

The figure shows the combination of swells directed at Grunters over a normal January. It is based on 2868 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast surf and wind right at the coastline so we have chosen the most applicable grid node based on what we know about Grunters. In the case of Grunters, the best grid node is 46 km away (29 miles).

The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing without direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These happened only 2% of the time. Green and yellow illustrate increasing swell sizes and red represents the biggest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how often that size swell happens.

The diagram indicates that the dominant swell direction, shown by the largest spokes, was SW, whereas the the prevailing wind blows from the SSE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Grunters and offshore. We combine these with the no surf category of the bar chart. To simplify things we don't show these in the rose plot. Because wind determines whether or not waves are clean enough to surf at Grunters, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. During a typical January, swells large enough to cause surfable waves at Grunters run for about 98% 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.