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)
'Physics is mathematical not because we know so much about the physical world, but because we know so little; it is only its mathematical properties that we can discover.'