Arroyo Laguna Swell Statistics, Settembre: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Arroyo Laguna that coincided with light winds or offshore conditions through a typical September. It is based on 2400 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. Green and yellow represent increasing swell sizes and red shows biggest swells greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how commonly that size swell happens.
The diagram implies that the most common swell direction, shown by the largest spokes, was SSW, whereas the the prevailing wind blows from the WNW. 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 4% of the time, equivalent to 1 days. Open sea swells exceeding >3m (>10ft) are unlikely to arise in a normal September. Taking into account the fraction of these swells that coincided with forecast offshore winds, and given the fact that Arroyo Laguna is exposed to open water swells, we think that that clean surf can be found at Arroyo Laguna about 4% of the time and that surf is messed up by onshore wind 37% of the time. This is means that we expect 12 days with waves in a typical September, 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.