THE BEAUFORT SCALE

The numbers of this scale correlate to the force of wind

0: CALM AND STILL <1 MILES PER HOUR

Smoke rises vertically.

1: LIGHT AIR 1 TO 3 MILES PER HOUR

Wind direction can be shown by smoke drift. The sea is rippled.

2: LIGHT BREEZE 4 TO 7 MILES PER HOUR

Leaves rustle on trees and wind is strong enough to move wind vanes.

3: GENTLE BREEZE 8 TO 12 MILES PER HOUR

Trees’ twigs constantly move. Small flags fly in the wind.

4: MODERATE BREEZE 13 TO 18 MILES PER HOUR

Dust and small branches can be lifted. Small waves form in the sea.

5: FRESH BREEZE 19 TO 24 MILES PER HOUR

Moderate-sized waves form. Small trees sway.

6: STRONG BREEZE 25 TO 31 MILES PER HOUR

Large branches move and large waves form.

7: NEAR GALE 32 TO 38 MILES PER HOUR

It becomes difficult to walk against the wind. Foam is blown across the sea.

8: GALE 39 TO 46 MILES PER HOUR

Twigs break from trees.

9: STRONG GALE 47 TO 54 MILES PER HOUR

Buildings can be damaged, such as roof slates being blown off.

10: STORM 55 TO 63 MILES PER HOUR

Trees are uprooted. Damage is caused to buildings and other structures.

11: VIOLENT STORM 64 TO 72 MILES PER HOUR

Widespread structural damage. The sea is covered in white foam and large waves.

12: HURRICANE 73+ MILES PER HOUR

Ocean foam and spray fills the air. There is significant structural damage.