Exercising outside in high temps can be a health hazard. Here's how to read your local index, according to a doctor, so you can stay safe.

New York state has entered its first heat wave of the summer - with highs expected to soar into the upper 90s and even past ...

"It's not the heat, it's the humidity." Actually, it's both, and that's where the National Weather Service's heat index comes in. Also known as the apparent temperature, the heat index is a number ...

What is heat index and how does it affect how stifling excessive heat feels?

The heat index, or apparent temperature, combines air temperature and humidity to indicate how hot it feels to the body. High humidity slows sweating, the body's natural cooling system, making ...

The metric of how hot the air actually feels has roots in a 1979 journal paper called “The Assessment of Sultriness.” By Andy Newman In recent days, you may have seen or heard many mentions of a ...

The heat and humidity will continue to build across Northeast Florida and Southeast Georgia this week. In fact, temperatures ...

The heat index, or apparent temperature, combines air temperature and relative humidity to indicate how hot it feels. High humidity slows sweating, the body's natural cooling system, making ...

Millions of Americans are facing heat advisories ahead of the July Fourth holiday as a major heat wave spreads across large ...

WASHINGTON — As the first heat wave of the season takes hold, people might be hearing a lot about "feels-like" temperatures. For example, WUSA9 meteorologists say at 4 p.m. Monday, the temperature ...

Above-average humidity in the greater Houston area is forecast to cause maximum heat indices above 100 degrees this weekend, ahead of heavy rain chances for Sunday and Monday, according to the ...