The graph illustrates how often and how strongly the wind blows from different directions through a typical northern hemisphere spring. The longest spokes point in the directions the wind most commonly blows from and the shade of blue indicates the strength, with dark blue showing the strongest winds. It is based on 4849 NWW3 forecasts of wind since since 2007, at 3hr intervals, for the closest NWW3 model node to Hellesto, located 17 km away (11 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 dominant wind at Hellesto blows from the WNW. If the rose plot shows a nearly round shape, it means there is no strong bias in wind direction at Hellesto. On the other hand, dominant spokes represent 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 spring, the model suggests that winds are light enough for the sea to be glassy (pale blue) about 7% of the time (6 days each northern hemisphere spring) and blows offshore 10% of the time (4 days in an average northern hemisphere spring). In a typical northern hemisphere spring winds stronger than >40kph (25mph) are expected on 3 days at Hellesto
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.