Beaufort Scale Chart |
Beaufort |
Avg
miles
per hour |
Avg km
per hour |
Knots |
Surroundings |
0
(calm) |
0 |
0 |
0-1 |
Smoke rises vertically and the sea is glassy or mirror smooth |
1
(light air) |
1.2-3 |
2-5 |
1-3 |
Smokes moves slightly with breeze and indicates the direction of wind |
2
(light breeze) |
3.7 7.5 |
6 12 |
4-6 |
You can feel wind on your face and hear the gentle movement of leaves on trees and shrubs |
3
(gentle breeze) |
8 12.5 |
13 20 |
7-10 |
Smoke will move horizontally and small branches start to sway. Wind extends a light flag |
4
(moderate breeze) |
13 18.6 |
21 30 |
11-16 |
Loose dust or sand on the ground will move and larger branches will sway, loose paper blows around, and fairly frequent whitecaps occur |
5
(fresh breeze) |
19.3 - 25 |
31 40 |
17-21 |
Surface waves form on water and small trees sway |
6
(strong breeze) |
25.5 - 31 |
41 - 50 |
22-27 |
Trees begin to bend with the force of the wind and causes whistling in telephone wires and some spray on the sea surface |
7
(moderate gale) |
32 - 38 |
51-61 |
28-33 |
large trees sway |
8
(fresh gale)
|
39 - 46 |
62-74 |
34-40 |
twigs break from trees, and long streaks of foam appear on the ocean |
9
(strong gale) |
47 - 55 |
75-89 |
41-47 |
branches break from trees |
10
(whole gale) |
56 - 64 |
90-103 |
48-55 |
trees are uprooted, and the sea takes on a foamy white appearance |
11
(storm) |
65 - 74 |
104-119 |
56-63 |
widespread damage |
12
(hurricane) |
75+ |
120+ |
64 + |
structural damage on land and intense storm waves at sea
|