Relative Humidity
What is relative humidity?
Relative humidity is the ratio of the water vapor actually in the air to the maximum amount the air could hold at that temperature, expressed as a percentage. For example, at 65 percent relative humidity, the air holds 65 percent of all the moisture it could possibly hold at that temperature and pressure. Because warmer air can hold more moisture, the same amount of water vapor produces a lower relative humidity as temperature rises. Think of it as how "full" the air is with water vapor.
Also known as: RH, relative humidity
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