Wind speeds
Mankind has never been able to standardise on how to measure wind speeds. As ever, the sensible way to do it is to use the SI method: metres per second (m/s). But there are many others. So here is an approximate table of equivalents…
Metres per second (m/s) |
Beaufort scale |
Kilometres per hour (km/h) |
Miles per hour (MPH) |
Knots |
Description |
|---|---|---|---|---|---|
<0.2 |
0 |
<1.8 |
<1.2 |
<1 |
Calm |
0.3-1.5 |
1 |
1.8-5.0 |
1.2-3.0 |
1-3 |
Light air |
1.6-3.3 |
2 |
6-11 |
4-7 |
4-6 |
Light breeze |
3.4-5.4 |
3 |
12-19 |
8-12 |
7-10 |
Gentle breeze |
5.5-7.9 |
4 |
20-28 |
13-17 |
11-15 |
Moderate Breeze |
8.0-10.7 |
5 |
29-38 |
18-24 |
16-21 |
Fresh breeze |
10.8-13.8 |
6 |
39-49 |
25-30 |
22-27 |
Strong breeze |
13.9-17.1 |
7 |
50-61 |
31-38 |
28-33 |
Near gale |
17.2-20.7 |
8 |
62-74 |
39-46 |
34-40 |
Gale |
20.8-24.4 |
9 |
75-88 |
47-54 |
41-47 |
Severe gale |
24.5-28.4 |
10 |
89-102 |
55-63 |
48-55 |
Storm |
28.5-32.6 |
11 |
103-107 |
64-73 |
56-63 |
Violent storm |
>32.7 |
12 |
>118 |
>74 |
>64 |
Hurricane |