What does the term heat index mean?

Question

What does the term heat index mean and how does is releate to the weather? Thanks

Answer 1

The heat index, like the wind chill factor, is an attempt to adjust the actual temperature to be more what it feels like.

If it is hot and dry where you are-- if you're in the desert--your perspiration will evaporate easily, taking heat energy from your skin to do so, and cooling you down.

If you are in a humid area like a swamp, your body sweats, but there is already so much water in the air that your sweat does not evaporate as easily. You feel hotter than you might think, just looking at the thermometer. You are also at greater danger from heat stroke, and moreover, you are soaked in sweat!

So the heat index takes two numbers: the temperature in degrees, and the humidity as a percentage of how much water the air can hold at that temperature. It adjusts the temperature for the humidity to get a number that more accurately reflects how human beings feel in that weather condition.

Answer 2

Heat index is what the role of humidity plays along with the temperature to determine what temperature it feels like to humans. Example a temp. of 97 plus a humidity of (X) will feel like 101 degrees outside. The index determines how different percentages of humidity changes the feeling of the temperature.