The short answer is both terms are different and describe different things about moisture in the air. The dew point is another temperature value. It is the temperature air needs to cool to become ...

Why is it that when it's raining, the relative humidity isn't 100%?

Dew point/relative humidity questions come up fairly often and this is a good one. Water vapor in the atmosphere is pretty important for deep-sky observing and photography. The atmosphere can only ...

The humidity has been critically low over the past few days, generally below 30%. What exactly is relative humidity, and how ...