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.

Good news: a weather forecast of 100 percent humidity doesn’t always mean it’s going to rain. Bad news: It might feel absolutely disgusting outside. The percentage of humidity is not measured by the ...

The first major heat wave of summer has enveloped much of the midwestern and eastern U.S. in a brutal “dome” of record temperatures and high humidity. The dome phenomenon happens when weather ...