25
GB
1
Light air
1.1 ~ 5km/h
Smoke drift indicates wind direction.
Leaves and wind vanes are stationary.
1 ~ 3 mph
1 ~ 3 knots
0.3 ~ 1.5 m/s
2
Light breeze
6 ~ 11 km/h
Wind felt on exposed skin. Leaves
rustle. Wind vanes begin to move.
4 ~ 7 mph
4 ~ 6 knots
1.6 ~ 3.3 m/s
3
Gentle breeze
12 ~ 19 km/h
Leaves and small twigs constantly
moving, light flags extended.
8 ~ 12 mph
7 ~ 10 knots
3.4 ~ 5.4 m/s
4
Moderate
breeze
20 ~ 28 km/h
Dust and loose paper raised. Small
branches begin to move.
13 ~ 17 mph
11 ~ 16 knots
5.5 ~ 7.9 m/s
5
Fresh breeze
29 ~ 38 km/h
Branches of a moderate size move.
Small trees in leaf begin to sway.
18 ~ 24 mph
17 ~ 21 knots
8.0 ~ 10.7 m/s
6
Strong breeze
39 ~ 49 km/h
Large branches in motion. Whistling
heard in overhead wires. Umbrella use
becomes difficult. Empty plastic bins tip
over.
25 ~ 30 mph
22 ~ 27 knots
10.8 ~ 13.8 m/s
7
High wind
50 ~ 61 km/h
Whole trees in motion. Effort needed to
walk against the wind.
31 ~ 38 mph
28 ~ 33 knots
13.9 ~ 17.1 m/s
8
Gale
62 ~ 74 km/h
Some twigs broken from trees.
Cars veer on road. Progress on foot is
seriously impeded
39 ~ 46 mph
34 ~ 40 knots
17.2 ~ 20.7 m/s
9
Strong gale
75 ~ 88 km/h
Some branches break off trees,
and some small trees blow over.
Construction /temporary signs and
barricades blow over.
47 ~ 54 mph
41 ~ 47 knots
20.8 ~ 24.4 m/s
10
Storm
89 ~ 102 km/h
Trees are broken off or uprooted,
structural damage likely.
55 ~ 63 mph
48 ~ 55 knots
24.5 ~ 28.4 m/s
Summary of Contents for 7802541
Page 74: ......
