During the hot, humid summer months, meteorologists often discuss the heat index instead of the actual air temperature. But how is the heat index calculated, and why is it more important than the air ...

"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 ...

Summer evenings in Tennessee are usually a welcome reprieve from the heat, but even that won't be the case this week. Communities across Tennessee have been dealing with heat indices reaching into the ...