Morro Negrito Swell Statistics, March: Surf with Light or Offshore Winds
This image shows only the swells directed at Morro Negrito that coincided with light winds or offshore conditions through a typical March and is based upon 2220 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 represents largest swells greater than >3m (>10ft). In either graph, the area of any colour is proportional to how commonly that size swell was forecast.
The diagram implies that the prevailing swell direction, shown by the longest spokes, was SSW, whereas the the most common wind blows from the NNE. 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 76% of the time, equivalent to 24 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal March but 11% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 11%, equivalent to (3 days). Taking into account the fraction of these swells that coincided with expected offshore winds, and given the fact that Morro Negrito is exposed to open water swells, we estimate that clean surf can be found at Morro Negrito about 76% of the time and that surf is spoilt by onshore wind 24% of the time. This is means that we expect 31 days with waves in a typical March, of which 24 days should be clean enough to surf.
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.