The rose diagram shows how often and how strongly the wind blows from different directions over a normal July. The biggest spokes point in the directions the wind most commonly blows from and the shade of blue indicates the strength, with deep blue showing the strongest winds. It is based on 1735 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Gullane Bay, located 53 km away (33 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 prevailing wind at Gullane Bay blows from the NE. If the rose graph shows a fairly circular pattern, it means there is no strong bias in wind direction at Gullane Bay. Converseley, dominant spokes show favoured directions, and the more deep blue, the stronger the wind. Spokes point in the direction the wind blows from. During a typical July, the model suggests that winds are light enough for the sea to be glassy (pale blue) about 8% of the time (2 days each July) and blows offshore 20% of the time (0 days in an average July). Over an average July winds exceeding >40kph (25mph) are not expected, but 2 have winds on the range 30-40 (19-25) at Gullane 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.