This image describes how commonly and how strongly the wind blows from different directions through a typical October. The longest spokes point in the directions the wind most commonly blows from and the shade of blue indicates the strength, with the darkest shade of blue strongest. It is based on 1736 NWW3 forecasts of wind since since 2006, at 3hr intervals, for the closest NWW3 model node to Santa Catarina, located 23 km away (14 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 Santa Catarina blows from the N. If the rose graph shows a fairly circular pattern, it means there is no strong bias in wind direction at Santa Catarina. Converseley, dominant spokes show favoured directions, and the more deep blue, the stronger the wind. Spokes point in the direction the wind blows from. Over an average October, the model suggests that winds are light enough for the sea to be glassy (the lightest shade of blue) about 4% of the time (1 days each October) and blows offshore just 27% of the time (8 days in an average October). In a typical October winds stronger than >40kph (25mph) are expected on 2 days at Santa Catarina
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.