The rose diagram shows the range of swells directed at Killer Point through a typical December, based on 1736 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 Killer Point, and at Killer Point the best grid node is 26 km away (16 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 represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These happened only 0.6% of the time. Green and yellow represent increasing swell sizes and biggest 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 occurs.

The diagram implies that the prevailing swell direction, shown by the biggest spokes, was NW, whereas the the prevailing wind blows from the NE. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Killer Point and away from the coast. We combine these with the no surf category of the bar chart. To keep it simple we don't show these in the rose graph. Because wind determines whether or not waves are good for surfing at Killer Point, you can view an alternative image that shows only the swells that were expected to coincide with glassy or offshore wind conditions. Over an average December, swells large enough to cause clean enough to surf waves at Killer Point run for about 87% 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.