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
Windspeed in MPH Description Visible Condition
0 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
