The rose diagram illustrates how frequently and how strongly the wind blows from different directions over a normal September. The biggest 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 deep blue. It is based on 1680 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Nigg Bay, located 15 km away (9 miles). There are insufficient recording stations world wide to use actual wind data. Without question some coastal places have very localized wind effects that would not be predicted by NWW3.
According to the model, the most common wind at Nigg Bay blows from the SE. If the rose diagram shows a close to circular outline, it means there is no strong bias in wind direction at Nigg Bay. Converseley, dominant spokes illustrate favoured directions, and the more deep blue, the stronger the wind. Spokes point in the direction the wind blows from. During a typical September, the model suggests that winds are light enough for the sea to be glassy (the lightest shade of blue) about 5% of the time (2 days each September) and blows offshore 17% of the time (4 days in an average September). Over an average September wind stronger than >40kph (25mph) was forecast for only a single days at Nigg Bay
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.