Heat/Humidity?

Question

Explain the popular adage, "It's not the heat, it's the humidity".

Answer 1

Humidity is basically moisture,so when you have heat and hot moisture in the air it makes it feel hotter than it really is. Just like in the winter it could be 25 degrees,but with high winds the chill factor makes it feel like 2 degrees.

Answer 2

First, a few fundamentals:

Humidity is a measure of the moisture (water) content in the air.

Evaporation of a liquid is affected by (among other things) temperature and the amount of the liquid already evaporated into the vapor phase.

Your body must maintain a certain core temperature to keep living.  To do this in hot weather, it secretes water in sweat.  The sweat evaporates.  When a liquid evaporates, there is a thermodynamic transfer of energy called the "heat of vaporization".  This is the amount of heat that it takes to evaporate the liquid.  This heat that is used to vaporize liquid is removed from your skin, and therefore your body.

When you sweat in high humidity, the sweat does not evaporate as effectively because there is already so much water in the air.  Therefore, less heat is removed from your skin through the heat of vaporization.  Your sweat just sits on your body without evaporating.

Answer 3

Because heat(heat wave) simply kills you whereas humidity tortures you.Getting killed is better than getting tortured continuously.

Answer 4

AccuWeather.com

Humidity level determines the comfort factor. 90' heat is hot enough...high humidity added to the heat index=DISCOMFORT. "It's not the {90'} heat {that is bothersome}...it's the{high level of} humidity{that is bothersome}." After hearing it said for the 15 millionth time, one might say, "It's not the heat, it's the STUPIDITY!"