Before revision: WMO Sea State Code Wave height Characteristics 0 Calm (glassy) 1 Calm (rippled) 2 Smooth (wavelets) 3 Slight 4 Moderate 5 Rough 6 Very rough 7 High 8 Very high 9 Over Phenomenal + Character of the sea swell 0.
After revision: graphic of WMO sea state codes, descriptions, and wave heights in metersWMO Sea State Code Wave height Characteristics 0 Calm (glassy) 1 Calm (rippled) 2 Smooth (wavelets) 3 Slight 4 Moderate 5 Rough 6 Very rough 7 High 8 Very high 9 Over Phenomenal + Character of the sea swell 0.