The rose diagram describes how commonly and how strongly the wind blows from different directions through a typical southern hemisphere winter. The longest spokes point in the directions the wind most commonly blows from and the shade of blue suggests the strength, with dark blue strongest. It is based on 5066 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Punta San Lorenzo, located 26 km away (16 miles). There are not enough recording stations world wide to use actual wind data. No doubt some coastal places have very localized wind effects that would not be predicted by NWW3.
According to the model, the prevailing wind at Punta San Lorenzo 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 Punta San Lorenzo. 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 southern hemisphere winter, the model suggests that winds are light enough for the sea to be glassy (the lightest shade of blue) about 0% of the time (0 days each southern hemisphere winter) and blows offshore just 0% of the time (0 days in an average southern hemisphere winter). During a typical southern hemisphere winter winds exceeding >40kph (25mph) are not expected, but 0 have winds on the range 30-40 (19-25) at Punta San Lorenzo
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.