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Japs ratings
Quality on a good day: 3.3
Consistency of Surf: 2.7
Difficulty Level: 3.7
Wind and Kite Surfing: 1.0
Crowds: 3.3

Overall: 3.2

See all 18 ratings

Based on 3 votes. Vote


Surf Report Feed

Japs Swell Statistics, September: Surf with Light or Offshore Winds

This image shows only the swells directed at Japs that coincided with light winds or offshore conditions over a normal September. It is based on 2880 predictions, one every 3 hours. The direction of the spokes show where quality surf generating swell comes from. Five colours show increasing wave sizes. The smallest swells, less than 0.5m (1.5 feet), high are coloured blue. Green and yellow illustrate increasing swell sizes and red illustrates the highest swells, greater than >3m (>10ft). In either graph, the area of any colour is proportional to how frequently that size swell occurs.

The diagram suggests that the most common swell direction, shown by the longest spokes, was SW, whereas the the dominant 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 41% of the time, equivalent to 12 days. Expect open water swells to exceed >3m (>10ft) 5% of the time (2 days). Taking into account the ratio of these swells that coincided with predicted offshore winds, and given the fact that Japs is exposed to open water swells, we calculate that clean surf can be found at Japs about 41% of the time and that surf is messed up by onshore wind 51% of the time. This is means that we expect 28 days with waves in a typical September, of which 12 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.