The figure describes how frequently 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 deep blue strongest. It is based on 1736 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Secret Harbour, located 25 km away (16 miles). There are insufficient 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 prevailing wind at Secret Harbour blows from the WSW. If the rose graph shows a fairly circular pattern, it means there is no strong bias in wind direction at Secret Harbour. By contrast, dominant spokes show favoured directions, and the more the darkest shade of 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 12% of the time (4 days each August) and blows offshore 35% of the time (11 days in an average August). Over an average August winds stronger than >40kph (25mph) are expected on 4 days at Secret Harbour
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.