Sea conditions outside lagoon 1.Slight = wave height 0.5 -1.25 metres 2.Moderate = wave 1.25 - 2.5 m 3.Rough = wave 2.5 - 4.0 m 4.Very rough = wave 4.0 - 6.0 m 5.High = wave 6.0 - 8.0 m 6.Very high = 8.0 - 12.0 m