Reference list of wind speeds to the wind intensity scale to Beaufort
|
Bft
|
m/s
|
km/h
|
MPH
|
Knots
|
Denomination of the wind intensity
|
Effects on inland
|
0 |
0-0.2 |
0-0.8 |
0-0.6 |
0-0.5 |
Quiet
|
Smoke rises in a straight line
|
1 |
0.3-1.5 |
0.9-5.5 |
0.7-3.5 |
0.6-3.0 |
Slight draught
|
Smoke indicates wind, weathercock still does not
|
2 |
1.6-3.3 |
5.6-12.1 |
3.6-7.5 |
3.1-6.5 |
Light breeze
|
Wind is noticeable on the face, weathercock is moving
|
3 |
3.4-5.4 |
12.2-19.6 |
7.6-12.2 |
6.6-10.5 |
Weak breeze
|
Leaves and thin branches move, wind stretches weathercock
|
4 |
5.5-7.9 |
19.7-28.5 |
12.3-17.8 |
10.6-15.5 |
Moderate breeze
|
Thin branches are moving, dust and paper are lifted
|
5 |
8.0-10.7 |
28.6-38.8 |
17.9-24.0 |
15.6-20.9 |
Fresh breeze
|
Small deciduous trees start swaying. On lakes white caps are forming
|
6 |
10.8-13.8 |
38.9-49.8 |
24.1-31.0 |
21.0-26.9 |
Strong breeze
|
Thick branches are moving, telegraph wires are whistling
|
7 |
13.9-17.1 |
49.9-61.7 |
31.1-38.3 |
27.0-33.3 |
Moderate gale
|
Whole trees are moving, hindrance in walking
|
8 |
17.2-20.7 |
61.8-74.6 |
38.4-46.4 |
33.4-40.3 |
Fresh gale
|
Wind breaks branches off trees
|
9 |
20.8-24.4 |
74.7-88.0 |
46.5-54.7 |
40.4-47.5 |
Strong gale
|
Minor damages to houses (roof tiles)
|
10 |
24.5-28.4 |
88.1-102.4 |
54.8-63.6 |
47.6-55.3 |
Full gale
|
Trees are being uprooted
|
11 |
28.5-32.6 |
102.5-117 |
63.7-73.0 |
55.4-63.4 |
Storm
|
(very rare in inland) storm damages
|
12-17 |
32.7-56 |
118+ |
73.1+ |
63.5+ |
Hurricane
|
|