BEAUFORT WIND SCALE

 

Beaufort

No.

Velocity

(knots)

Pressure

lb/sq ft

Sea Description
0 Less than 1 0 Calm
1

1 - 3

0.01

Light Air

2 4 - 6

0.08

Light Breeze

3 7 - 10

0.28

Gentle Breeze

4

11 - 16

0.67

Moderate Breeze

5

17-21

1.31

Fresh Breeze

6

20 - 27

2.3

Strong Breeze

7

28 - 33

3.6

Moderate Gale

8

34 - 40

5.4

Fresh Gale

9

41 - 47

7.7

Strong Gale

10

48 - 55

10.5

Whole Gale

11 56 - 63 14.0

Storm

12 over 64 17 and above

Hurricane