Otago Peninsula - Allans Beach Swell Statistics, Spring: All Swell – Any Wind
This image shows the combination of swells directed at Otago Peninsula - Allans Beach through an average southern hemisphere spring, based on 7252 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast surf and wind right at the shore so we have chosen the best grid node based on what we know about Otago Peninsula - Allans Beach. In the case of Otago Peninsula - Allans Beach, the best grid node is 21 km away (13 miles).
The rose diagram shows the distribution of swell directions and swell sizes, 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 occurred only 30% of the time. Green and yellow represent 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 longest spokes, was S, whereas the the prevailing wind blows from the WNW. Because the wave model grid is out to sea, sometimes a strong offshore wind blows largest waves away from Otago Peninsula - Allans Beach and offshore. We group these with the no surf category of the bar chart. To simplify things we don't show these in the rose graph. Because wind determines whether or not waves are good for surfing at Otago Peninsula - Allans Beach, 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 southern hemisphere spring, swells large enough to cause clean enough to surf waves at Otago Peninsula - Allans Beach run for about 70% 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.