What is the difference between the old and the new Wind Chill Indices?
Okay, so far, no one has actually asked us this question, but it seemed like a likely candidate for the FAQ when the change took place. The wind chill formula was revised in 2001 to attempt to make the Wind Chill Index (WCI) more representative of reality. The previous formula gave values that were generally considered to be too cold. For details, please see the NOAA article on this subject. Follow the link to the PDF chart to find the actual equation for computing the new index.
