Relative humidity is a simple concept as weather phenomena go – but it has significant, far-reaching consequences for how we must take care of ourselves on a hot or wet day. Humidity is the amount of ...

It’s a T-shirt kind of day in Washington, DC: 85 degrees with 63 percent humidity. We all know those numbers mean hot, but what exactly does that humidity percentage tell us? And why should we care?

When referring to the mugginess of the air, meteorologists will point to dew point rather than relative humidity. Relative humidity is indeed a measure of how much moisture is in the air relative to ...