π¨ Meteorology & Maritime Sea State
Beaufort Wind Force Scale ($0 - 12$) & Wind Speed Converter
Convert atmospheric wind speed across $\text{Beaufort Number}$ ($0 - 12+$), $\text{Knots}$ ($\text{kt}$), $\text{km/h}$, $\text{mph}$, and $\text{m/s}$ with official WMO maritime sea state observations.
π Force 0 (Calm < 1 kt)
πͺ Force 4 (Moderate Breeze 11-16 kt)
β΅ Force 6 (Strong Breeze 22-27 kt)
π Force 8 (Gale 34-40 kt)
βοΈ Force 10 (Storm 48-55 kt)
π Force 12 (Hurricane β₯ 64 kt)
Input Wind Speed
Beaufort Wind Force
Force 6 β Strong Breeze
π Maritime & Land Observable Effects:
Sea: Large waves begin to form; extensive white foam crests (wave height 3.0β4.0 m / 10β13 ft).
Land: Large branches in motion; whistling heard in telegraph wires; umbrellas used with difficulty.
π‘ Empirical Beaufort Formula:
$$v(\text{m/s}) = 0.836 \cdot B^{3/2} \implies B \approx \left(\frac{v}{0.836}\right)^{2/3}$$
The Beaufort Wind Scale Standard Reference Chart
| Force | Description | Knots (kt) | km/h | mph | Wave Height |
|---|---|---|---|---|---|
| 0 | Calm | < 1 | < 2 | < 1 | 0 m (Flat) |
| 1 | Light Air | 1 β 3 | 2 β 5 | 1 β 3 | 0.1 m |
| 2 | Light Breeze | 4 β 6 | 6 β 11 | 4 β 7 | 0.2 β 0.3 m |
| 3 | Gentle Breeze | 7 β 10 | 12 β 19 | 8 β 12 | 0.6 β 1.0 m |
| 4 | Moderate Breeze | 11 β 16 | 20 β 28 | 13 β 18 | 1.0 β 1.5 m |
| 5 | Fresh Breeze | 17 β 21 | 29 β 38 | 19 β 24 | 2.0 β 2.5 m |
| 6 | Strong Breeze | 22 β 27 | 39 β 49 | 25 β 31 | 3.0 β 4.0 m |
| 7 | Near Gale | 28 β 33 | 50 β 61 | 32 β 38 | 4.0 β 5.5 m |
| 8 | Gale | 34 β 40 | 62 β 74 | 39 β 46 | 5.5 β 7.5 m |
| 9 | Strong Gale | 41 β 47 | 75 β 88 | 47 β 54 | 7.0 β 10.0 m |
| 10 | Storm | 48 β 55 | 89 β 102 | 55 β 63 | 9.0 β 12.5 m |
| 11 | Violent Storm | 56 β 63 | 103 β 117 | 64 β 72 | 11.5 β 16.0 m |
| 12+ | Hurricane Force | β₯ 64 | β₯ 118 | β₯ 73 | β₯ 14.0 m |