Wind Chill Factor
Wind Velocity in Miles Per Hour

5
10
15
20
25
30
35
40
45
50
55
T
e
m
p
e
r
a
t
u
r
e
50°
48°
40°
36°
32°
30°
28°
27°
26°
25°
25°
25°
45°
43°
34°
29°
25°
22°
20°
19°
18°
17°
17°
17°
40°
37°
28°
22°
18°
15°
13°
11°
10°
35°
32°
22°
15°
11°
30°
27°
16°
- 3°
- 5°
- 6°
- 7°
- 7°
- 7°
25°
22°
10°
- 3°
- 7°
- 10°
- 12°
- 14°
- 15°
- 15°
- 15°
20°
16°
- 5°
- 11°
- 15°
- 18°
- 20°
- 22°
- 23°
- 23°
- 23°
15°
11°
- 3°
- 12°
- 18°
- 22°
- 25°
- 28°
- 30°
- 31°
- 31°
- 31°
10°
- 9°
- 18°
- 25°
- 30°
- 33°
- 36°
- 38°
- 39°
- 39°
- 39°
- 15°
- 25°
- 32°
- 37°
- 41°
- 44°
- 46°
- 47°
- 47°
- 47°
- 5°
- 21°
- 32°
- 39°
- 44°
- 48°
- 51°
- 53°
- 55°
- 55°
- 55°
- 5°
- 10°
- 27°
- 38°
- 46°
- 52°
- 56°
- 59°
- 61°
- 63°
- 63°
- 63°
- 10°
- 15°
- 34°
- 45°
- 53°
- 59°
- 64°
- 67°
- 69°
- 71°
- 71°
- 71°
- 15°
- 21°
- 40°
- 52°
- 60°
- 67°
- 71°
- 75°
- 77°
- 79°
- 79°
- 79°
- 20°
- 26°
- 46°
- 59°
- 68°
- 74°
- 79°
- 83°
- 85°
- 87°
- 87°
- 87°
- 25°
-31°
- 52°
- 65°
- 75°
- 82°
- 87°
- 90°
- 93°
- 95°
- 95°
- 95°

The wind chill factor is a measure of how quickly your body loses heat. It is not the same as an actual thermometer reading of the same number. For example, if the temperature is 40°F and the wind speed is 20 miles per hour, the wind chill factor is 18°F, but water will not freeze.

The Effects of Wind Chill
30° F or greater.

Chilly. Generally unpleasant.

15° F to - 30° F

Cold. Unpleasant.

0° F to -15° F

Very cold. Very unpleasant.

- 0° F to - 20° F

Bitter cold. Frostbite possible.

- 20° F to - 60° F

Extremely cold. Frostbite likely. Outdoor activety becomes dangerous.

- 60° F or less

Frigidly cold. Exposed flesh will freeze within 30 seconds.


To use the chart, locate the air temperature along the left column and the wind speed along the top. The cell where the two intersect is the wind chill factor.

How the wind chill factor is computed. For wind speeds under 5 miles per hour, there is no significant wind chill factor and for wind speeds above 45 miles per hour the wind has no further appreciable effect. For wind speeds between 5 mph and 45 mph, the following formula may be used to calculate the wind chill factor -- where t is the temperature in degrees and v is the wind velocity in miles per hour.