Why does it seem colder in the South vs. North of 60?

Wednesday, September 26, 2007
A couple of posts ago when we were all discussing the relative temperatures of where we all lived, Juanasi posted the question of why the cold temperatures in the North and South (although, they may be the same) seem different. Well... I have an answer from Bernard Duguay, a Meteorological Inquiry Specialist with the MSC National Inquiry Response Team Environment Canada.

"The perception of how cold it is, is affected by the humidity and by the wind. If the humidity is low, a temperature of -30 degrees will not feel as cold as a temperature of -30 degrees when the humidity is higher, provided that there is no wind, as wind affects more the perception of how cold it is more than humidity. However, please note that the temperature itself is not affected by humidity or wind, only the perception of how cold it is.

The reason for this perception is because even on cold days our bodies are perspiring. The sweat is evaporated into the layer of air next to our skins...cooling its temperature and making us feel colder. Drier air allows this evaporation to happen quickly almost unnoticed by us. The addition of our sweat to the layer of air next to our skin is so small as to produce little noticeable cooling. In higher humidity, the moisture lingers, dampens our skin (ever so slightly) and the evaporational cooling is much more noticeable. Thus, for an equal temperature, we feel colder when it's humid than when it's dry."

So there we have it. Why it seems colder in the South vs. the North although it is the same temperature according to the thermometer.