This chart illustrates how frequently and how strongly the wind blows from different directions over a normal December. The biggest spokes point in the directions the wind most commonly blows from and the shade of blue suggests the strength, with the strongest winds shown by deep blue. It is based on 1736 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Rock Wave, located 18 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 prevailing wind at Rock Wave blows from the S. If the rose diagram shows a close to circular outline, it means there is no strong bias in wind direction at Rock Wave. 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 December, the model suggests that winds are light enough for the sea to be glassy (light blue) about 4% of the time (1 days each December) and blows offshore just 6% of the time (2 days in an average December). Over an average December wind stronger than >40kph (25mph) was predicted for only a single days at Rock Wave
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.