Statistiques de Houle pour Arugam Bay, Février: Vagues avec Vents Légers ou Favorables.
The rose diagram shows only the swells directed at Arugam Bay that coincided with light winds or offshore conditions through a typical February. It is based on 2102 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 the biggest swells, greater than >3m (>10ft). In both graphs, the area of any colour is proportional to how commonly that size swell occurs.
The diagram implies that the dominant swell direction, shown by the largest spokes, was S, whereas the the prevailing wind blows from the NE. 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 47% of the time, equivalent to 13 days. Open sea swells exceeding >3m (>10ft) are unlikely to happen in a normal February but 18% of the time you can expect swell in the range 1.3-2m (4-6.5ft) 18%, equivalent to (5 days). Taking into account the proportion of these swells that coincided with predicted offshore winds, and given the fact that Arugam Bay is exposed to open water swells, we calculate that clean surf can be found at Arugam Bay about 47% of the time and that surf is blown out by onshore wind 26% of the time. This is means that we expect 20 days with waves in a typical February, of which 13 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.