The Disaster Center Page
  Conversion table for knots to miles per hour
Conversion table for
knots to miles per hour   
KTS to MPH
5
Knots
=
5.8
MPH
10
Knots
=
11.5
MPH
15
Knots
=
17.3
MPH
20
Knots
=
23.0
MPH
25
Knots
=
28.8
MPH
30
Knots
=
34.6
MPH
35
Knots
=
40.3
MPH
40
Knots
=
46.1
MPH
45
Knots
=
51.8
MPH
50
Knots
=
57.6
MPH
55
Knots
=
63.4
MPH
60
Knots
=
69.1
MPH
65
Knots
=
74.9
MPH
70
Knots
=
80.6
MPH
75
Knots
=
86.4
MPH
80
Knots
=
92.2
MPH
85
Knots
=
97.9
MPH
90
Knots
=
103.7
MPH
95
Knots
=
109.4
MPH
100
Knots
=
115.2
MPH
105
Knots
=
121.0
MPH
110
Knots
=
126.7
MPH
115
Knots
=
132.5
MPH
120
Knots
=
138.2
MPH
125
Knots
=
144.0
MPH
130
Knots
=
149.8
MPH
135
Knots
=
155.5
MPH
140
Knots
=
161.3
MPH
145
Knots
=
167.0
MPH
150
Knots
=
172.8
MPH
Beaufort Wind Scale
Windspeed
in MPH
 Description - Visible Condition 
Calm smoke rises vertically 
1 - 4  Light air direction of wind shown by smoke but not by wind vanes 
4 - 7  Light breeze wind felt on face; leaves rustle; ordinary wind vane moved by wind 
8 - 12  Gentle breeze leaves and small twigs in constant motion; wind extends light flag 
13 - 18  Moderate breeze raises dust and loose paper; small branches are moved 
19 - 24  Fresh breeze small trees in leaf begin to sway; crested wavelets form on inland water 
25 - 31  Strong breeze large branches in motion; telephone wires whistle; umbrellas used with difficulty 
32 - 38  Moderate gale whole trees in motion; inconvenience in walking against wind 
39 - 46  Fresh gale breaks twigs off trees; generally impedes progress 
47 - 54  Strong gale slight structural damage occurs; chimney pots and slates removed 
55 - 63  Whole gale trees uprooted; considerable structural damage occurs 
64 - 72  Storm very rarely experienced; accompanied by widespread damage 
73+  Hurricane devastation occurs 


Windspeed  in MPH Description Visible Condition 
Calm Smoke rises vertically 
1 - 4  Light Air Direction of wind shown by smoke but not by wind vanes 
4 - 7  Light Breeze Wind felt on face; leaves rustle; ordinary wind vane moved by wind 
8 - 12  Gentle Breeze Leaves and small twigs in constant motion; wind extends light flag 
13 - 18  Moderate Breeze Raises dust, loose paper and; small branches are moved 
19 - 24  Fresh Breeze Small trees in leaf begin to sway; crested wavelets form on inland water 
25 - 31  Strong Breeze Large branches in motion; telephone wires whistle; umbrellas used with difficulty 
32 - 38  Moderate Gale Whole trees in motion; inconvenience in walking against wind 
39 - 46  Fresh Gale Breaks twigs off trees
47 - 54  Strong Gale Slight structural damage occurs; chimney pots and slates removed 
55 - 63  Whole Gale Trees uprooted; considerable structural damage occurs 
64 - 72  Storm Very rarely experienced; accompanied by widespread damage 
73+  Hurricane Devastation occurs