Noosa - Alexandria Bay Swell Statistics, Summer: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Noosa - Alexandria Bay that coincided with light winds or offshore conditions over a normal southern hemisphere summer. It is based on 6931 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 shows biggest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the dominant swell direction, shown by the longest spokes, was SE, whereas the the prevailing wind blows from the E. 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 0.7% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal southern hemisphere summer. Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Noosa - Alexandria Bay is exposed to open water swells, we estimate that clean surf can be found at Noosa - Alexandria Bay about 0.7% of the time and that surf is messed up by onshore wind 17% of the time. This is means that we expect 16 days with waves in a typical southern hemisphere summer, of which 1 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.