The graph describes how frequently and how strongly the wind blows from different directions through a typical northern hemisphere summer. The largest spokes point in the directions the wind most commonly blows from and the shade of blue indicates the strength, with the strongest winds shown by the darkest shade of blue. It is based on 5057 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to La Garde Guerin, located 41 km away (25 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 prevailing wind at La Garde Guerin blows from the WNW. If the rose diagram shows a close to circular outline, it means there is no strong bias in wind direction at La Garde Guerin. On the other hand, dominant spokes illustrate favoured directions, and the more the darkest shade of blue, the stronger the wind. Spokes point in the direction the wind blows from. Over an average northern hemisphere summer, the model suggests that winds are light enough for the sea to be glassy (the lightest shade of blue) about 11% of the time (10 days each northern hemisphere summer) and blows offshore 17% of the time (4 days in an average northern hemisphere summer). In a typical northern hemisphere summer winds stronger than >40kph (25mph) are expected on 2 days at La Garde Guerin
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.