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Tables of Wind Chill Values for Various Temperatures and Windspeeds

Wind chill is an attempt to quantify the cooling effect of wind and is based on the rate of heat loss from exposed human skin caused by the combined effects of wind and temperature. As wind speed increases, the body cools at a faster rate, causing a drop in skin temperature and eventually the internal body temperature. Wind greatly increases the dangers of frostbite and hypothermia to anyone not well protected.

The term "wind chill" originates from the Antarctic explorer Paul A. Siple, who coined it a 1939 dissertation "Adaptation of the Explorer to the Climate of Antarctica". During the 1940s Siple and Charles F. Passel conducted experiments on the time needed to freeze water in a plastic cylinder that was exposed to the elements. They found that the time depends on how warm the water is at the beginning, the outside temperature, and the wind speed.

The US military developed a wind chill standard during World War II. They were looking for a quick and easy way for military officers to make decisions about outdoor maneuvers in arctic cold. However their research was flawed and in their hurried attempt to arrive at a formula they ignored some data that didn't seem to fit. Therefore their results have errors and a particular wind chill value reached by a certain combination of temperature and wind can feel quite different from a wind chill of the same value reached by a different combination.

In response to this, for the winter of 2001, the US National Weather Service replaced the old wind chill factor with the wind chill index to take into consideration these errors. The current formula used to compute wind chill is:

    Iwc = 13.12 + 0.6215 Tc + ( 0.4275 Tc - 35.75) v 0.16

    where:
        Iwc = Wind Chill Index
        Tc = Temperature in Degrees Celsius
        v = Wind Velocity in kmh-1

NB. The formulas used to calculate wind chill for these tables are not valid for wind speeds outside the range of approximately 1.8 ms-1 to 25ms-1. Wind chill values also assume no impact from the sun (ie. a clear night sky) since bright sunshine may increase the wind chill temperature.

Windchill Values :: Celsius vs km per hour
Windspeed (km/h) Air Temperature (°Celsius)
8 6 4 2 0 -2 -4 -6 -8 -10 -12 -14 -16 -18 -20 -22 -24 -26 -28 -30
10 6.2 3.9 1.5 -0.9 -3.3 -5.7 -8.1 -10.5 -12.9 -15.3 -17.7 -20.0 -22.4 -24.8 -27.2 -29.6 -32.0 -34.4 -36.8 -39.2
15 5.4 3.0 0.5 -2.0 -4.4 -6.9 -9.3 -11.8 -14.3 -16.7 -19.2 -21.7 -24.1 -26.6 -29.1 -31.5 -34.0 -36.5 -38.9 -41.4
20 4.9 2.3 -0.2 -2.7 -5.2 -7.8 -10.3 -12.8 -15.3 -17.9 -20.4 -22.9 -25.4 -28.0 -30.5 -33.0 -35.5 -38.0 -40.6 -43.1
25 4.4 1.8 -0.8 -3.3 -5.9 -8.5 -11.1 -13.6 -16.2 -18.8 -21.3 -23.9 -26.5 -29.0 -31.6 -34.2 -36.8 -39.3 -41.9 -44.5
30 4.0 1.4 -1.3 -3.9 -6.5 -9.1 -11.7 -14.3 -16.9 -19.5 -22.1 -24.7 -27.3 -30.0 -32.6 -35.2 -37.8 -40.4 -43.0 -45.6
35 3.6 1.0 -1.7 -4.3 -7.0 -9.6 -12.2 -14.9 -17.5 -20.2 -22.8 -25.5 -28.1 -30.8 -33.4 -36.0 -38.7 -41.3 -44.0 -46.6
40 3.3 0.6 -2.0 -4.7 -7.4 -10.1 -12.7 -15.4 -18.1 -20.8 -23.4 -26.1 -28.8 -31.5 -34.1 -36.8 -39.5 -42.2 -44.8 -47.5
45 3.0 0.3 -2.4 -5.1 -7.8 -10.5 -13.2 -15.9 -18.6 -21.3 -24.0 -26.7 -29.4 -32.1 -34.8 -37.5 -40.2 -42.9 -45.6 -48.3
50 2.8 0.0 -2.7 -5.4 -8.1 -10.9 -13.6 -16.3 -19.0 -21.8 -24.5 -27.2 -29.9 -32.7 -35.4 -38.1 -40.9 -43.6 -46.3 -49.0
55 2.5 -0.2 -3.0 -5.7 -8.5 -11.2 -14.0 -16.7 -19.5 -22.2 -25.0 -27.7 -30.5 -33.2 -36.0 -38.7 -41.5 -44.2 -46.9 -49.7
60 2.3 -0.5 -3.2 -6.0 -8.8 -11.5 -14.3 -17.1 -19.9 -22.6 -25.4 -28.2 -30.9 -33.7 -36.5 -39.2 -42.0 -44.8 -47.5 -50.3
65 2.1 -0.7 -3.5 -6.3 -9.1 -11.8 -14.6 -17.4 -20.2 -23.0 -25.8 -28.6 -31.4 -34.2 -36.9 -39.7 -42.5 -45.3 -48.1 -50.9
70 1.9 -0.9 -3.7 -6.5 -9.3 -12.1 -14.9 -17.7 -20.5 -23.4 -26.2 -29.0 -31.8 -34.6 -37.4 -40.2 -43.0 -45.8 -48.6 -51.4
75 1.7 -1.1 -3.9 -6.7 -9.6 -12.4 -15.2 -18.0 -20.9 -23.7 -26.5 -29.3 -32.2 -35.0 -37.8 -40.6 -43.5 -46.3 -49.1 -51.9
80 1.6 -1.3 -4.1 -7.0 -9.8 -12.6 -15.5 -18.3 -21.2 -24.0 -26.9 -29.7 -32.5 -35.4 -38.2 -41.1 -43.9 -46.7 -49.6 -52.4
85 1.4 -1.5 -4.3 -7.2 -10.0 -12.9 -15.7 -18.6 -21.5 -24.3 -27.2 -30.0 -32.9 -35.7 -38.6 -41.5 -44.3 -47.2 -50.0 -52.9
90 1.3 -1.6 -4.5 -7.4 -10.2 -13.1 -16.0 -18.9 -21.7 -24.6 -27.5 -30.3 -33.2 -36.1 -39.0 -41.8 -44.7 -47.6 -50.4 -53.3

Windchill Values :: Celsius vs metres per second
Windspeed (m/s) Air Temperature (°Celsius)
8 6 4 2 0 -2 -4 -6 -8 -10 -12 -14 -16 -18 -20 -22 -24 -26 -28 -30
2 19.4 17.7 15.9 14.2 12.5 10.8 9.0 7.3 5.6 3.9 2.1 0.4 -1.3 -3.0 -4.8 -6.5 -8.2 -10.0 -11.7 -13.4
4 7.9 5.9 3.9 1.9 -0.1 -2.1 -4.1 -6.1 -8.1 -10.1 -12.1 -14.1 -16.1 -18.1 -20.1 -22.1 -24.1 -26.1 -28.1 -30.1
6 -0.1 -2.3 -4.5 -6.7 -8.9 -11.0 -13.2 -15.4 -17.6 -19.8 -22.0 -24.2 -26.4 -28.6 -30.8 -33.0 -35.2 -37.4 -39.6 -41.8
8 -6.3 -8.6 -11.0 -13.3 -15.7 -18.0 -20.4 -22.7 -25.0 -27.4 -29.7 -32.1 -34.4 -36.8 -39.1 -41.4 -43.8 -46.1 -48.5 -50.8
10 -11.4 -13.8 -16.3 -18.8 -21.2 -23.7 -26.2 -28.6 -31.1 -33.6 -36.0 -38.5 -41.0 -43.4 -45.9 -48.3 -50.8 -53.3 -55.7 -58.2
12 -15.6 -18.2 -20.8 -23.3 -25.9 -28.5 -31.0 -33.6 -36.2 -38.7 -41.3 -43.9 -46.4 -49.0 -51.6 -54.1 -56.7 -59.3 -61.8 -64.4
14 -19.3 -21.9 -24.6 -27.3 -29.9 -32.6 -35.2 -37.9 -40.5 -43.2 -45.8 -48.5 -51.1 -53.8 -56.5 -59.1 -61.8 -64.4 -67.1 -69.7
16 -22.5 -25.2 -27.9 -30.6 -33.4 -36.1 -38.8 -41.6 -44.3 -47.0 -49.8 -52.5 -55.2 -58.0 -60.7 -63.4 -66.1 -68.9 -71.6 -74.3
18 -25.2 -28.0 -30.8 -33.6 -36.4 -39.2 -42.0 -44.8 -47.6 -50.4 -53.2 -56.0 -58.8 -61.6 -64.4 -67.2 -70.0 -72.8 -75.6 -78.4
20 -27.7 -30.5 -33.4 -36.2 -39.1 -41.9 -44.8 -47.6 -50.5 -53.4 -56.2 -59.1 -61.9 -64.8 -67.6 -70.5 -73.3 -76.2 -79.0 -81.9
22 -29.8 -32.7 -35.6 -38.5 -41.4 -44.3 -47.2 -50.2 -53.1 -56.0 -58.9 -61.8 -64.7 -67.6 -70.5 -73.4 -76.3 -79.2 -82.1 -85.0
24 -31.7 -34.7 -37.6 -40.6 -43.5 -46.5 -49.4 -52.4 -55.3 -58.3 -61.2 -64.2 -67.1 -70.1 -73.0 -76.0 -78.9 -81.9 -84.8 -87.8

Windchill Values :: Fahrenheit vs miles per hour
Windspeed (mph) Air Temperature (°Fahrenheit)
45 40 35 30 25 20 15 10 5 0 -5 -10 -15 -20 -25 -30
5 42.3 36.5 30.6 24.7 18.9 13.0 7.1 1.2 -4.6 -10.5 -16.4 -22.3 -28.1 -34.0 -39.9 -45.7
10 39.8 33.6 27.4 21.2 15.1 8.9 2.7 -3.5 -9.7 -15.9 -22.1 -28.3 -34.5 -40.7 -46.9 -53.1
15 38.2 31.8 25.4 19.0 12.6 6.2 -0.2 -6.6 -13.0 -19.4 -25.8 -32.2 -38.6 -45.0 -51.4 -57.8
20 37.0 30.5 23.9 17.4 10.8 4.2 -2.3 -8.9 -15.4 -22.0 -28.6 -35.1 -41.7 -48.2 -54.8 -61.4
25 36.1 29.4 22.7 16.0 9.3 2.6 -4.0 -10.7 -17.4 -24.1 -30.8 -37.5 -44.1 -50.8 -57.5 -64.2
30 35.3 28.5 21.7 14.9 8.1 1.3 -5.5 -12.3 -19.1 -25.9 -32.7 -39.4 -46.2 -53.0 -59.8 -66.6
35 34.5 27.7 20.8 13.9 7.0 0.1 -6.8 -13.6 -20.5 -27.4 -34.3 -41.2 -48.1 -54.9 -61.8 -68.7
40 33.9 26.9 20.0 13.0 6.1 -0.9 -7.9 -14.8 -21.8 -28.8 -35.7 -42.7 -49.7 -56.6 -63.6 -70.6
45 33.3 26.3 19.3 12.2 5.2 -1.8 -8.9 -15.9 -23.0 -30.0 -37.0 -44.1 -51.1 -58.1 -65.2 -72.2
50 32.8 25.7 18.6 11.5 4.4 -2.7 -9.8 -16.9 -24.0 -31.1 -38.2 -45.3 -52.4 -59.5 -66.6 -73.7

Windchill Values :: Fahrenheit vs knots
Windspeed (knots) Air Temperature (°Fahrenheit)
45 40 35 30 25 20 15 10 5 0 -5 -10 -15 -20 -25 -30
5 41.9 35.9 30.0 24.1 18.1 12.2 6.2 0.3 -5.6 -11.6 -17.5 -23.4 -29.4 -35.3 -41.2 -47.2
10 39.3 33.0 26.8 20.5 14.2 8.0 1.7 -4.6 -10.8 -17.1 -23.4 -29.6 -35.9 -42.2 -48.4 -54.7
15 37.7 31.2 24.7 18.2 11.7 5.3 -1.2 -7.7 -14.2 -20.7 -27.1 -33.6 -40.1 -46.6 -53.0 -59.5
20 36.4 29.8 23.2 16.5 9.9 3.2 -3.4 -10.0 -16.7 -23.3 -29.9 -36.6 -43.2 -49.9 -56.5 -63.1
25 35.4 28.7 21.9 15.1 8.4 1.6 -5.2 -11.9 -18.7 -25.5 -32.2 -39.0 -45.8 -52.5 -59.3 -66.1
30 34.6 27.7 20.9 14.0 7.1 0.2 -6.6 -13.5 -20.4 -27.3 -34.1 -41.0 -47.9 -54.8 -61.6 -68.5
35 33.9 26.9 19.9 13.0 6.0 -1.0 -7.9 -14.9 -21.9 -28.8 -35.8 -42.8 -49.7 -56.7 -63.7 -70.6
40 33.2 26.2 19.1 12.1 5.0 -2.0 -9.1 -16.1 -23.2 -30.2 -37.3 -44.3 -51.4 -58.4 -65.5 -72.5
45 32.7 25.5 18.4 11.3 4.1 -3.0 -10.1 -17.2 -24.4 -31.5 -38.6 -45.7 -52.9 -60.0 -67.1 -74.2
50 32.1 24.9 17.7 10.5 3.3 -3.8 -11.0 -18.2 -25.4 -32.6 -39.8 -47.0 -54.2 -61.4 -68.6 -75.8

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This page first created by Craig Porter: 2008.