11.
instinct hb
WIND INDICATOR
FORCE
0
1
2
3
4
5
6
7
8
Calm: smoke rises vertically
Light air
Light breeze
Gentle wind
Moderate wind : leaves in motion, light flags extended
Fresh wind : small trees begin to sway
Sand blows on the beach
White-capped waves
Gale, trouble walking
DESCRIPTION
KNOTS
<1
1-3
4-6
7-10
11-16
17-21
22-27
28-33
34-40
KM/H
<1
1-5
6-11
12-19
20-28
29-38
39-49
50-61
62-74