The rose diagram shows only the swells directed at Long Beach Peninsula that coincided with light winds or offshore conditions over a normal northern hemisphere spring. It is based on 5140 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 both graphs, the area of any colour is proportional to how frequently that size swell occurs.
The diagram suggests that the dominant swell direction, shown by the longest spokes, was W, whereas the the most common wind blows from the WSW. 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 35% of the time, equivalent to 32 days. Expect open water swells to exceed >3m (>10ft) 6% of the time (5 days). Taking into account the proportion of these swells that coincided with forecast offshore winds, and given the fact that Long Beach Peninsula is exposed to open water swells, we calculate that clean surf can be found at Long Beach Peninsula about 35% of the time and that surf is spoilt by onshore wind 59% of the time. This is means that we expect 86 days with waves in a typical northern hemisphere spring, of which 32 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.