Extreme levels of heat and humidity are forecast to spread across the country over the next two weeks, blanketing the Southwest, Midwest, and East Coast with high temperatures beginning this June 19 ...

The heat index is a measure of how hot it really feels on your body when relative humidity is factored in with the actual air ...

Have you ever wondered why meteorologists on TV focus on the dewpoint temperature and not relative humidity? Or, have you ...

The temperature on any given summer day may be in the 80s or 90s. So why does it feel so much hotter and oppressive at times? That's the heat index doing its thing. Here's how it works: What is the ...

Relative humidity measures how much moisture is in the air compared to how much it could hold at a given temperature. It is simply the dew point temperature divided by the air temperature, times 100.

Michigan's heat wave this week will feel even warmer because of high humidity. Here's how the heat index works.