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

Popular usage of “humidity” refers to a measure of the atmosphere’s water content or the amount of moisture in the air. What many may not realize is that there are a number of different humidity ...

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 ...

Given the Earth’s present weather and climate, it is an impossibility. Some water vapor is always present in the air, even if only in trace amounts. Nearly all of the Earth’s surface passes water ...