Weather Forecast

The Beaufort Scale

Wind ForceDescriptionkm/hmphknotsSpecifications
0Calm<1<1<1Smoke rises vertically
1Light Air01-0501-0301-03Direction shown by smoke drift but not by wind vanes
2Light Breeze06-1104-0704-06Wind felt on face; leaves rustle; wind vane moved by wind
3Gentle Breeze12-1908-1207-10Leaves and small twigs in constant motion; light flags extended
4Moderate Breeze20-2813-1811-16Raises dust and loose paper; small branches moved.
5Fresh Breeze29-3819-2417-21Small trees in leaf begin to sway; crested wavelets form on inland waters.
6Strong Breeze38-4925-3122-27Large branches in motion; whistling heard in telegraph wires; umbrellas used with difficulty.
7Near Gale50-6132-3828-33Whole trees in motion; inconvenience felt when walking against the wind.
8Gale62-7439-4634-40Twigs break off trees; generally impedes progress.
9Strong Gale75-8847-5441-47Slight structural damage (chimney pots and slates removed).
10Storm89-10255-6348-55Seldom experienced inland; trees uprooted; considerable structural damage
11Violent Storm103-11764-7256-63Very rarely experienced; accompanied by widespread damage.
12Hurricane118 plus73 plus64 plusDevastation
The Beaufort Scale is an empirical measure that relates wind speed to observed conditions at sea or on land. Its full name is the Beaufort wind force scale.