The figure describes how commonly and how strongly the wind blows from different directions through a typical southern hemisphere summer. The biggest spokes point in the directions the wind most commonly blows from and the shade of blue indicates the strength, with the darkest shade of blue showing the strongest winds. It is based on 5047 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Whangaehu River Mouth, located 51 km away (32 miles). There are too few recording stations world wide to use actual wind data. No doubt some coastal places have very localized wind effects that would not be predicted by NWW3.
According to the model, the most common wind at Whangaehu River Mouth blows from the W. If the rose graph shows a fairly circular pattern, it means there is no strong bias in wind direction at Whangaehu River Mouth. On the other hand, dominant spokes represent favoured directions, and the more deep blue, the stronger the wind. Spokes point in the direction the wind blows from. Over an average southern hemisphere summer, the model suggests that winds are light enough for the sea to be glassy (the lightest shade of blue) about 7% of the time (6 days each southern hemisphere summer) and blows offshore 16% of the time (0 days in an average southern hemisphere summer). In a typical southern hemisphere summer winds stronger than >40kph (25mph) are expected on 4 days at Whangaehu River Mouth
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.