A phenomenon called the Wind Chill factor makes us feel colder in winter than the air temperature really is. This is due to the interaction of air temperature and wind on the human body, which is already giving off heat. Both temperature and wind cause heat loss from body surfaces. A combination of cold and wind makes a body feel colder than the actual temperature.
You may hear it mentioned quite often on the news during the winter months. How do news weather persons know that when there is a 10mph wind with a temperature of 5 degrees F that the real temperature we feel is -10 degrees F?
There is a specific formula that can be used to calculate wind chill.
Use this calculator to determine the actual wind chill given the air temperature and wind speed.