|
The
Beaufort Wind Scale
|
|
Force
|
Wind
Speed
(knots)
|
Description
|
Observations
& wave size.
|
|
0
|
0
|
Calm
|
Sea
like a mirror.
|
|
1
|
1-3
|
Light
Air
|
Small
ripples without crests.
0.1m
|
|
2
|
4-6
|
Light
Breeze
|
Small
wavelets. Crests do not break. 0.2m
|
|
3
|
7-10
|
Gentle
Breeze
|
Large
wavelets. Crests begin to break. 0.6m
|
|
4
|
11-16
|
Moderate
Breeze
|
Small
waves. Fairly frequent white horses. 1.0m
|
|
5
|
17-21
|
Fresh
Breeze
|
Moderate
waves. Many white horses. 2.0m
|
|
6
|
22-27
|
Strong
Breeze
|
Large
waves. White crests everywhere. 3.0m
|
|
7
|
28-33
|
Near
Gale
|
Sea
heaps up. White foam begins to be blown in streaks. 4.0m
|
|
8
|
34-40
|
Gale
|
Moderately
high waves of greater length. Foam blown in well marked streaks.
5.5m
|
|
9
|
41-47
|
Strong
Gale
|
High
waves. Dense streaks of foam. Crests begin to roll over. Spray
affects visibility. 7.0m
|
|
10
|
48-55
|
Storm
|
Very
high waves with long overhanging crests. Dense white streaks
of foam . Rolling sea becomes heavy. Visibility reduced. 9.0m
|
|
11
|
56-63
|
Violent
Storm
|
Mountainous
waves. Sea completely covered with foam. Visibility affected.
12.0m
|
|
12
|
64+
|
Hurricane
|
Sea
completely white with driving spray. Air filled with foam
and spray. Visibilty seriosly reduced. 14m+
|