The rose diagram describes how often and how strongly the wind blows from different directions over a normal southern hemisphere autumn. The biggest spokes point in the directions the wind most commonly blows from and the shade of blue implies the strength, with the darkest shade of blue showing the strongest winds. It is based on 4858 NWW3 forecasts of wind since since 2007, at 3hr intervals, for the closest NWW3 model node to Quarantine, located 25 km away (16 miles). There are insufficient recording stations world wide to use actual wind data. Invevitably some coastal places have very localized wind effects that would not be predicted by NWW3.
According to the model, the most common wind at Quarantine blows from the SW. If the rose graph shows a fairly circular pattern, it means there is no strong bias in wind direction at Quarantine. By contrast, dominant spokes illustrate favoured directions, and the more dark blue, the stronger the wind. Spokes point in the direction the wind blows from. During a typical southern hemisphere autumn, the model suggests that winds are light enough for the sea to be glassy (pale blue) about 13% of the time (12 days each southern hemisphere autumn) and blows offshore 30% of the time (27 days in an average southern hemisphere autumn). Over an average southern hemisphere autumn winds stronger than >40kph (25mph) are expected on 6 days at Quarantine
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.