Wind Force Table - Wind Force, Wind Speed and Designation
The wind force is measured in Beaufort, Bft. This scale is used worldwide up to level 12. The expansion with levels 13 to 17 is only used in China and Taiwan, where such wind forces can occur during typhoons. There are several other locally used storm scales, the most important of which is the Saffir-Simpson Hurricane Scale from the US National Hurricane Center. There are other special scales for tropical cyclones, which can reach strengths similar to hurricanes.
Wind forces on the Beaufort scale
| Bft | km/h | Designation | Sea |
|---|---|---|---|
| 0 | 0 - 1 | Calm | - |
| 1 | 1 - 5 | Light air | Ripples |
| 2 | 6 - 11 | Light breeze | Small wavelets |
| 3 | 12 - 19 | Gentle breeze | Large wavelets |
| 4 | 20 - 28 | Moderate breeze | Small waves |
| 5 | 29 - 38 | Fresh breeze | Moderate waves |
| 6 | 39 - 49 | Strong breeze | Large waves |
| 7 | 50 - 61 | High wind, moderate gale, near gale | White foam |
| 8 | 62 - 74 | Gale, fresh gale | Moderately high waves |
| 9 | 75 - 88 | Strong/severe gale | High waves |
| 10 | 89 - 102 | Storm, whole gale | Very high waves |
| 11 | 103 - 117 | Violent storm | Exceptionally high waves |
| 12 | 118 - (133) | Hurricane force | Completely white |
| 13 | 134 - 149 | Typhoon | |
| 14 | 150 - 166 | Typhoon | |
| 15 | 167 - 183 | Typhoon | |
| 16 | 184 - 202 | Typhoon | |
| 17 | 203 - | Typhoon |
Saffir Simpson Hurricane Scale
| Designation | km/h |
|---|---|
| Tropical depression | - 63 |
| Tropical storm | 63 - 118 |
| Hurricane category 1 | 119 - 153 |
| Hurricane category 2 | 154 - 177 |
| Hurricane category 3 | 178 - 208 |
| Hurricane category 4 | 209 - 251 |
| Hurricane category 5 | 251 - |
Speeds are given in kilometers per hour. Meters per second are used scientifically, miles per hour are used in the USA and knots are used on the high seas.
The highest linear wind speed recorded to date was measured by cyclone Olivia on April 10, 1996 on Barrow Island, Western Australia: 408 km/h. The rotation speed of a tornado can be even higher, maximum values of up to 500 km/h can be reached here.
Physics commonly uses SI units. Here is a calculator to convert lengths, temperature, pressure, speed and other units.