Kuta Beach Swell Statistics, Winter: All Swell – Any Wind
This image describes the variation of swells directed at Kuta Beach through a typical southern hemisphere winter, based on 7208 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the coast so we have chosen the optimum grid node based on what we know about Kuta Beach. In the case of Kuta Beach, the best grid node is 36 km away (22 miles).
The rose diagram describes the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These were forecast only 1.0% of the time. Green and yellow show increasing swell sizes and highest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the dominant swell direction, shown by the biggest spokes, was SSW, whereas the the dominant wind blows from the ESE. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Kuta Beach 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 Kuta Beach, 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 southern hemisphere winter, swells large enough to cause surfable waves at Kuta Beach run for about 99% 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.