Acid Drops Swell Statistics, Janeiro: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Acid Drops that coincided with light winds or offshore conditions over a normal January. It is based on 2372 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. Green and yellow show increasing swell sizes and red illustrates the biggest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the prevailing swell direction, shown by the longest spokes, was SW, whereas the the prevailing wind blows from the ENE. The chart at the bottom shows the same thing but without direction information. For example, swells larger than 1.5 feet (0.5m) coincided with good wind conditions 0.2% of the time, equivalent to 0 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal January. Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Acid Drops is exposed to open water swells, we estimate that clean surf can be found at Acid Drops about 0.2% of the time and that surf is messed up by onshore wind 1.8% of the time. This is means that we expect 1 days with waves in a typical January, of which 0 days should be surfable.
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.