The graph shows how commonly and how strongly the wind blows from different directions over a normal August. The biggest spokes point in the directions the wind most commonly blows from and the shade of blue indicates the strength, with dark blue strongest. It is based on 1736 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Rapid Bay, located 15 km away (9 miles). There are insufficient recording stations world wide to use actual wind data. Without question some coastal places have very localized wind effects that would not be predicted by NWW3.
According to the model, the most common wind at Rapid Bay blows from the SW. If the rose diagram shows a close to circular outline, it means there is no strong bias in wind direction at Rapid Bay. By contrast, dominant spokes show favoured directions, and the more deep blue, the stronger the wind. Spokes point in the direction the wind blows from. During a typical August, the model suggests that winds are light enough for the sea to be glassy (pale blue) about 7% of the time (2 days each August) and blows offshore 15% of the time (0 days in an average August). Over an average August winds stronger than >40kph (25mph) are expected on 2 days at Rapid Bay
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.