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Jacobs Bay ratings
Quality on a good day: 4.0
Consistency of Surf: 3.0
Difficulty Level: 1.0
Crowds: 3.0

Overall: 3.2

See all 18 ratings

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Surf Report Feed

Jacobs Bay Swell Statistics, Autumn: All Swell – Any Wind

The rose diagram shows the combination of swells directed at Jacobs Bay through an average southern hemisphere autumn, based on 8682 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coast so we have chosen the best grid node based on what we know about Jacobs Bay. In this particular case the best grid node is 37 km away (23 miles).

The rose diagram shows the distribution of swell sizes and swell direction, while the graph at the bottom shows the same thing but lacks direction information. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. These were forecast only 4% of the time. Green and yellow show 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 dominant swell direction, shown by the largest spokes, was SW, whereas the the prevailing wind blows from the SSW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Jacobs Bay and offshore. We combine these 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 clean enough to surf at Jacobs Bay, you can load a different image that shows only the swells that were forecast to coincide with glassy or offshore wind conditions. In a typical southern hemisphere autumn, swells large enough to cause surfable waves at Jacobs Bay run for about 96% 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.