Beaufort Wind Scale


The Beaufort Scale, used throughout the marine world, has developed over many years since it was first devised by Admiral Francis Beaufort in 1806. Today, the Beaufort scale is defined for seamen in terms of sea state. It's emphasis is more on the observed effect of the wind, rather than the actual wind speed.

Currently :   

Force
#

Wind
Type

Wind
Speed

Wave
Height

0


Calm

< 1
< 1
< 1

 
 

mph
km/h
kts

0
0

 
 

m
ft

  On Sea : Flat  On Land : Calm. Smoke rises vertically

Force
#

Wind
Type

Wind
Speed

Wave
Height

1


Light air

1 - 3
1.1 - 5.5
1 - 2

 
 

mph
km/h
kts

0 - 0.2
0 - 1

 
 

m
ft

  On Sea : Ripples without crests  On Land : Wind motion visible in smoke

Force
#

Wind
Type

Wind
Speed

Wave
Height

2


Light breeze

4 - 7
5.6 - 11
3 - 6

 
 

mph
km/h
kts

0.2 - 0.5
1 - 2

 
 

m
ft

  On Sea : Small wavelets. Crests of glassy appearance, not breaking  On Land : Wind felt on exposed skin. Leaves rustle

Force
#

Wind
Type

Wind
Speed

Wave
Height

3


Gentle breeze

8 - 12
12 - 19
7 - 10

 
 

mph
km/h
kts

0.5 - 1
2 - 3.5

 
 

m
ft

  On Sea : Large wavelets. Crests begin to break; scattered whitecaps  On Land : Leaves and smaller twigs in constant motion

Force
#

Wind
Type

Wind
Speed

Wave
Height

4


Moderate breeze

13 - 17
20 - 28
11 - 15

 
 

mph
km/h
kts

1 - 2
3.5 - 6

 
 

m
ft

  On Sea : Small waves with breaking crests. Fairly frequent white horses  On Land : Dust and loose paper raised. Small branches begin to move

Force
#

Wind
Type

Wind
Speed

Wave
Height

5


Fresh breeze

18 - 24
29 - 38
16 - 20

 
 

mph
km/h
kts

2 - 3
6 - 9

 
 

m
ft

  On Sea : Moderate waves of some length. Many white horses. Small amounts of spray  On Land : Branches of a moderate size move. Small trees begin to sway

Force
#

Wind
Type

Wind
Speed

Wave
Height

6


Strong breeze

25 - 30
39 - 49
21 - 26

 
 

mph
km/h
kts

3 - 4
9 - 13

 
 

m
ft

  On Sea : Long waves begin to form. White foam crests are very frequent. Some airborne spray is present  On Land : Large branches in motion. Whistling heard in overhead wires. Umbrella use becomes difficult. Empty plastic rubbish bins tip over

Force
#

Wind
Type

Wind
Speed

Wave
Height

7


High wind, moderate gale, near gale

31 - 38
50 - 61
27 - 33

 
 

mph
km/h
kts

4 - 5.5
13 - 18

 
 

m
ft

  On Sea : Sea heaps up. Some foam from breaking waves is blown into streaks along wind direction. Moderate amounts of airborne spray  On Land : Whole trees in motion. Effort needed to walk against the wind. Swaying of skyscrapers may be felt, especially by people on upper floors

Force
#

Wind
Type

Wind
Speed

Wave
Height

8


Gale, fresh gale

39 - 46
62 - 74
34 - 40

 
 

mph
km/h
kts

5.5 - 7.5
18 - 24.6

 
 

m
ft

  On Sea : Moderately high waves with breaking crests forming spindrift. Well-marked streaks of foam are blown along wind direction. Considerable airborne spray  On Land : Some twigs broken from trees. Cars veer on road. Progress on foot is seriously impeded

Force
#

Wind
Type

Wind
Speed

Wave
Height

9


Strong gale

47 - 54
75 - 88
41 - 47

 
 

mph
km/h
kts

7.5 - 10
24.6 - 32.8

 
 

m
ft

  On Sea : High waves whose crests sometimes roll over. Dense foam is blown along wind direction. Large amounts of airborne spray may begin to reduce visibility  On Land : Some branches break off trees, and some small trees blow over. Construction/temporary signs and barricades blow over. Damage to circus tents and canopies

Force
#

Wind
Type

Wind
Speed

Wave
Height

10


Storm, whole gale

55 - 63
89 - 102
48 - 55

 
 

mph
km/h
kts

10 - 12.5
32.8 - 41

 
 

m
ft

  On Sea : Very high waves with overhanging crests. Large patches of foam from wave crests give the sea a white appearance. Considerable tumbling of waves with heavy impact. Large amounts of airborne spray reduce visibility  On Land : Trees are broken off or uprooted, saplings bent and deformed. Poorly attached asphalt shingles and shingles in poor condition peel off roofs

Force
#

Wind
Type

Wind
Speed

Wave
Height

11


Violent storm

64 - 72
103 - 117
56 - 63

 
 

mph
km/h
kts

12.5 - 16
41 - 52.5

 
 

m
ft

  On Sea : Exceptionally high waves. Very large patches of foam, driven before the wind, cover much of the sea surface. Very large amounts of airborne spray severely reduce visibility  On Land : Widespread damage to vegetation. Many roofing surfaces are damaged; asphalt tiles that have curled up and/or fractured due to age may break away completely

Force
#

Wind
Type

Wind
Speed

Wave
Height

12


Hurricane

≥ 73
≥ 118
≥ 64

 
 

mph
km/h
kts

≥ 17
≥ 52.5

 
 

m
ft

  On Sea : Huge waves. Sea is completely white with foam and spray. Air is filled with driving spray, greatly reducing visibility  On Land : Very widespread damage to vegetation. Some windows may break; mobile homes and poorly constructed sheds and barns are damaged. Debris may be hurled about

This information is automatically generated, is not quality controlled and may not update in a timely manner. You accept all risks and responsibility for losses, damages, costs and other consequences resulting directly or indirectly from using this site and any information or material available from it. Tide data is not to be used for the purpose of port operation or general navigation..

Powered by Davis Vantage Pro2 (6163AU)  and   CumulusMX   v 3.18.0 (b3190)   MXUI Template v 2.2.4 by  Silver Acorn     Valid HTML5

BOM