# Humidex and Windchill Calculators

## Humidex Calculator

Humidex = (air temperature) + h
h = (0.5555)*(e - 10.0);
e = 6.11 * exp(5417.7530 * ((1/273.16) - (1/dewpoint)))

 Temperature: °C Relative humidity: % °C

## Windchill Calculator

Windchill Temperature = 0.045*(5.2735*SQROOT(W) + 10.45 - 0.2778*W)*(T - 33.0)+33
WCF = 1.1626*(5.2735*SQROOT(W) + 10.45 - 0.2778*W)*(33.0 - T)

where:
ET = equivalent temperature (degrees Celsius)
WCF = wind chill factor (Watts per square metre)
SQROOT = square root function
W = wind speed (Km/hr)
T = air temperature (degrees Celsius)
(Source: Weather University of Waterloo)

 Temperature: °C Wind speed: km/hr °C

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