This image shows only the swells directed at Red Bluff that coincided with light winds or offshore conditions over a normal February. It is based on 1584 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. Green and yellow show increasing swell sizes and red illustrates the largest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell was forecast.
The diagram indicates that the dominant swell direction, shown by the longest spokes, was ESE (which was the same as the most common wind direction). 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 20% of the time, equivalent to 6 days. Open sea swells exceeding >3m (>10ft) are unlikely to occur in a normal February but 6% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 6%, equivalent to (2 days). Taking into account the ratio of these swells that coincided with expected offshore winds, and given the fact that Red Bluff is exposed to open water swells, we calculate that clean surf can be found at Red Bluff about 20% of the time and that surf is spoilt by onshore wind 54% of the time. This is means that we expect 21 days with waves in a typical February, of which 6 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.