LOUISVILLE, Ky. — It’s that time of the year again when heat and humidity cause sweltering temperatures across Kentucky and southern Indiana. You’ve likely heard about the heat index mentioned once or ...

Some hot days feel even worse thanks to high humidity, trapped heat and dew points. Cities are especially vulnerable. By Nazaneen Ghaffar Nazaneen Ghaffar is a reporter on The Times’s weather team. It ...

Relative humidity is not a good way to tell if we have muggy air on the way. Here’s why. The key word in relative humidity is ...

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 ...