The figure illustrates how frequently and how strongly the wind blows from different directions through a typical January. 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 dark blue. It is based on 1728 NWW3 forecasts of wind since since 2007, at 3hr intervals, for the closest NWW3 model node to Porto Batel, located 23 km away (14 miles). There are too few 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 Porto Batel 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 Porto Batel. On the other hand, dominant spokes represent favoured directions, and the more dark blue, the stronger the wind. Spokes point in the direction the wind blows from. Over an average January, the model suggests that winds are light enough for the sea to be glassy (the lightest shade of blue) about 12% of the time (4 days each January) and blows offshore 37% of the time (11 days in an average January). During a typical January winds stronger than >40kph (25mph) are expected on 4 days at Porto Batel
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.