I read an article about wind chill last winter. Apparently, we have been calculating it all wrong for a long time--based on some studies in the arctic in the early 1900s. It has been recalculated and lowered as an effect.
This caused problems because People for many years, for some a lifetime, have been basing winter clothing on wind chill temps. Now what might have been -20 with wind chill is -5 with wind chill thus making people wear too thin of a coat.
The best thing to do is go by what the temperature is. Real feel and wind chill is actually dependent on the person somewhat. Some are sensitive to either or both extremes so a temperature of 80 can kill someone while others are fine up to 100. Same for cold temps.