Andrew Molera State Park Swell Statistics, March: Surf with Light or Offshore Winds
The rose diagram shows only the swells directed at Andrew Molera State Park 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 illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. Green and yellow show increasing swell sizes and largest swells greater than >3m (>10ft) are shown in red. In each graph, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the prevailing swell direction, shown by the largest spokes, was WNW, whereas the the most common wind blows from the NW. 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 36% of the time, equivalent to 11 days. Open water swells exceeding >3m (>10ft) only happen 4% of the time in a typical March, equivalent to just one day but 20% of the time we expect swell in the range 2-3m (6.5-10ft) 20%, equivalent to (6 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Andrew Molera State Park is exposed to open water swells, we estimate that clean surf can be found at Andrew Molera State Park about 36% of the time and that surf is spoilt by onshore wind 60% of the time. This is means that we expect 30 days with waves in a typical March, of which 11 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.