While we've been sweltering through summer, the National Weather Service has been preparing for the cold season. They recently announced that starting with this coming winter, forecasters will be using a new Wind Chill Index that's been redesigned to give a more accurate reading of the cooling effect of wind on your skin.

The Wind Chill Index that's been in use since the 1940s is based on experiments done in the Antarctic with bags of water exposed to different combinations of wind and cold. The updated index relies more on modern science's understanding of how the skin loses heat, particularly the face which is the part of the body most frequently exposed to the air. For most of the combinations of wind and cold that we experience around here, the new wind chill values are higher than the old values, in some cases by as much as 15^oF. For example, a temperature of 25^oF with a wind of 20 mph gave a wind chill of -3^oF in the old index but +11^oF in the new.

Scientists from the U.S. and Canadian Weather Services and the International Society of Biometeorology worked on the redesigned index. They actually conducted clinical trials that helped to verify the accuracy of the new numbers. This was an overhaul that was long overdue.