<Table> <Tr> <Th> Beaufort number </Th> <Th> Description </Th> <Th> Wind speed </Th> <Th> Wave height </Th> <Th> Sea conditions </Th> <Th> Land conditions </Th> <Th> Sea state photo </Th> <Th> Associated warning flag </Th> </Tr> <Tr> <Th> 0 </Th> <Td> Calm </Td> <Td> < 1 km / h </Td> <Td> 0 m </Td> <Td> Sea like a mirror </Td> <Td> Smoke rises vertically . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> < 1 mph </Td> </Tr> <Tr> <Td> < 1 knot </Td> <Td> 0 ft </Td> </Tr> <Tr> <Td> < 0.3 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Light air </Td> <Td> 1 -- 5 km / h </Td> <Td> 0 -- 0.2 m </Td> <Td> Ripples with appearance of scales are formed , without foam crests </Td> <Td> Direction shown by smoke drift but not by wind vanes . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 1 -- 3 mph </Td> </Tr> <Tr> <Td> 1 -- 3 knots </Td> <Td> 0 -- 1 ft </Td> </Tr> <Tr> <Td> 0.3 -- 1.5 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Light breeze </Td> <Td> 6 -- 11 km / h </Td> <Td> 0.2 -- 0.5 m </Td> <Td> Small wavelets still short but more pronounced ; crests have a glassy appearance but do not break </Td> <Td> Wind felt on face ; leaves rustle ; wind vane moved by wind . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 4 -- 7 mph </Td> </Tr> <Tr> <Td> 4 -- 6 knots </Td> <Td> 1 -- 2 ft </Td> </Tr> <Tr> <Td> 1.6 -- 3.3 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Gentle breeze </Td> <Td> 12 -- 19 km / h </Td> <Td> 0.5 -- 1 m </Td> <Td> Large wavelets ; crests begin to break ; foam of glassy appearance ; perhaps scattered white horses </Td> <Td> Leaves and small twigs in constant motion ; light flags extended . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 8 -- 12 mph </Td> </Tr> <Tr> <Td> 7 -- 10 knots </Td> <Td> 2 -- 3.5 ft </Td> </Tr> <Tr> <Td> 3.4 -- 5.5 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Moderate breeze </Td> <Td> 20 -- 28 km / h </Td> <Td> 1 -- 2 m </Td> <Td> Small waves becoming longer ; fairly frequent white horses </Td> <Td> Raises dust and loose paper ; small branches moved . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 13 -- 18 mph </Td> </Tr> <Tr> <Td> 11 -- 16 knots </Td> <Td> 3.5 -- 6 ft </Td> </Tr> <Tr> <Td> 5.5 -- 7.9 m / s </Td> </Tr> <Tr> <Th> 5 </Th> <Td> Fresh breeze </Td> <Td> 29 -- 38 km / h </Td> <Td> 2 -- 3 m </Td> <Td> Moderate waves taking a more pronounced long form ; many white horses are formed ; chance of some spray </Td> <Td> Small trees in leaf begin to sway ; crested wavelets form on inland waters . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 19 -- 24 mph </Td> </Tr> <Tr> <Td> 17 -- 21 knots </Td> <Td> 6 -- 9 ft </Td> </Tr> <Tr> <Td> 8 -- 10.7 m / s </Td> </Tr> <Tr> <Th> 6 </Th> <Td> Strong breeze </Td> <Td> 39 -- 49 km / h </Td> <Td> 3 -- 4 m </Td> <Td> Large waves begin to form ; the white foam crests are more extensive everywhere ; probably some spray </Td> <Td> Large branches in motion ; whistling heard in telegraph wires ; umbrellas used with difficulty . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 25 -- 31 mph </Td> </Tr> <Tr> <Td> 22 -- 27 knots </Td> <Td> 9 -- 13 ft </Td> </Tr> <Tr> <Td> 10.8 -- 13.8 m / s </Td> </Tr> <Tr> <Th> 7 </Th> <Td> High wind , moderate gale , near gale </Td> <Td> 50 -- 61 km / h </Td> <Td> 4 -- 5.5 m </Td> <Td> Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind ; spindrift begins to be seen </Td> <Td> Whole trees in motion ; inconvenience felt when walking against the wind . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 32 -- 38 mph </Td> </Tr> <Tr> <Td> 28 -- 33 knots </Td> <Td> 13 -- 19 ft </Td> </Tr> <Tr> <Td> 13.9 -- 17.1 m / s </Td> </Tr> <Tr> <Th> 8 </Th> <Td> Gale , fresh gale </Td> <Td> 62 -- 74 km / h </Td> <Td> 5.5 -- 7.5 m </Td> <Td> Moderately high waves of greater length ; edges of crests break into spindrift ; foam is blown in well - marked streaks along the direction
<Table> <Tr> <Th> Beaufort number </Th> <Th> Description </Th> <Th> Wind speed </Th> <Th> Wave height </Th> <Th> Sea conditions </Th> <Th> Land conditions </Th> <Th> Sea state photo </Th> <Th> Associated warning flag </Th> </Tr> <Tr> <Th> 0 </Th> <Td> Calm </Td> <Td> < 1 km / h </Td> <Td> 0 m </Td> <Td> Sea like a mirror </Td> <Td> Smoke rises vertically . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> < 1 mph </Td> </Tr> <Tr> <Td> < 1 knot </Td> <Td> 0 ft </Td> </Tr> <Tr> <Td> < 0.3 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Light air </Td> <Td> 1 -- 5 km / h </Td> <Td> 0 -- 0.2 m </Td> <Td> Ripples with appearance of scales are formed , without foam crests </Td> <Td> Direction shown by smoke drift but not by wind vanes . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 1 -- 3 mph </Td> </Tr> <Tr> <Td> 1 -- 3 knots </Td> <Td> 0 -- 1 ft </Td> </Tr> <Tr> <Td> 0.3 -- 1.5 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Light breeze </Td> <Td> 6 -- 11 km / h </Td> <Td> 0.2 -- 0.5 m </Td> <Td> Small wavelets still short but more pronounced ; crests have a glassy appearance but do not break </Td> <Td> Wind felt on face ; leaves rustle ; wind vane moved by wind . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 4 -- 7 mph </Td> </Tr> <Tr> <Td> 4 -- 6 knots </Td> <Td> 1 -- 2 ft </Td> </Tr> <Tr> <Td> 1.6 -- 3.3 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Gentle breeze </Td> <Td> 12 -- 19 km / h </Td> <Td> 0.5 -- 1 m </Td> <Td> Large wavelets ; crests begin to break ; foam of glassy appearance ; perhaps scattered white horses </Td> <Td> Leaves and small twigs in constant motion ; light flags extended . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 8 -- 12 mph </Td> </Tr> <Tr> <Td> 7 -- 10 knots </Td> <Td> 2 -- 3.5 ft </Td> </Tr> <Tr> <Td> 3.4 -- 5.5 m / s </Td> </Tr> <Tr> <Th> </Th> <Td> Moderate breeze </Td> <Td> 20 -- 28 km / h </Td> <Td> 1 -- 2 m </Td> <Td> Small waves becoming longer ; fairly frequent white horses </Td> <Td> Raises dust and loose paper ; small branches moved . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 13 -- 18 mph </Td> </Tr> <Tr> <Td> 11 -- 16 knots </Td> <Td> 3.5 -- 6 ft </Td> </Tr> <Tr> <Td> 5.5 -- 7.9 m / s </Td> </Tr> <Tr> <Th> 5 </Th> <Td> Fresh breeze </Td> <Td> 29 -- 38 km / h </Td> <Td> 2 -- 3 m </Td> <Td> Moderate waves taking a more pronounced long form ; many white horses are formed ; chance of some spray </Td> <Td> Small trees in leaf begin to sway ; crested wavelets form on inland waters . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 19 -- 24 mph </Td> </Tr> <Tr> <Td> 17 -- 21 knots </Td> <Td> 6 -- 9 ft </Td> </Tr> <Tr> <Td> 8 -- 10.7 m / s </Td> </Tr> <Tr> <Th> 6 </Th> <Td> Strong breeze </Td> <Td> 39 -- 49 km / h </Td> <Td> 3 -- 4 m </Td> <Td> Large waves begin to form ; the white foam crests are more extensive everywhere ; probably some spray </Td> <Td> Large branches in motion ; whistling heard in telegraph wires ; umbrellas used with difficulty . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 25 -- 31 mph </Td> </Tr> <Tr> <Td> 22 -- 27 knots </Td> <Td> 9 -- 13 ft </Td> </Tr> <Tr> <Td> 10.8 -- 13.8 m / s </Td> </Tr> <Tr> <Th> 7 </Th> <Td> High wind , moderate gale , near gale </Td> <Td> 50 -- 61 km / h </Td> <Td> 4 -- 5.5 m </Td> <Td> Sea heaps up and white foam from breaking waves begins to be blown in streaks along the direction of the wind ; spindrift begins to be seen </Td> <Td> Whole trees in motion ; inconvenience felt when walking against the wind . </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> 32 -- 38 mph </Td> </Tr> <Tr> <Td> 28 -- 33 knots </Td> <Td> 13 -- 19 ft </Td> </Tr> <Tr> <Td> 13.9 -- 17.1 m / s </Td> </Tr> <Tr> <Th> 8 </Th> <Td> Gale , fresh gale </Td> <Td> 62 -- 74 km / h </Td> <Td> 5.5 -- 7.5 m </Td> <Td> Moderately high waves of greater length ; edges of crests break into spindrift ; foam is blown in well - marked streaks along the direction
description given to zero on the beaufort scale
description given to zero on the beaufort scale
Calm
Calm