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About WMO Beaufort Code Table

Beaufort Code

Code Appearance of sea if fetch and duraction of the blow have been sufficient to develop the sea fully Description
00 Sea like a mirror Calm
01 Ripples with the appearance of scales are formed, but without foam crests Light air
02 Small wavelets; crests have a glassy appearance and do not break Light breeze
03 Large wavelets; crests begin to break; foam of glassy appearance; perhaps scattered white horses Gentle breeze
04 Small waves, becoming longer; fairly frequent white horses Moderate breeze
05 Moderate waves; many white horses are formed (chance of some spray) Fresh breeze
06 Large waves; white foam crests everywhere (probably some spray) Strong breeze
07 Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind Near gale
08 Moderately high waves; edges of crests begin to break into the spindrift; foam is blown in well-marked streaks along the direction of the wind Gale
09 High waves; dense streaks of foam along wind; crests begin to topple, tumble and roll over; spray may affect visibility Strong gale
10 Very high waves with long overhanging crests; foam in great patches blown in dense white streaks along wind; sea surface takes a white appearance; tumbling becomes heavy and shock-like; visibility affected Storm
11 Exceptionally high waves (medium sized ships may be lost to view behind waves); sea covered with long white patches of foam lying along the wind; everywhere edges of crests are blown into froth; visibility affected Violent storm
12 Air is filled with foam and spray; sea completely white with driving spray; visibility seriously affected Hurricane