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The reason why it's sticky: What is the dew point?

11:00
9 September 2023

The reason it's sticky
What is the dew point?

dew-point-shutterstock

Feel like the air has been muggy recently? You're not wrong, the dew point this week has been relatively high, making things uncomfortable. So what is it?

The dew point is the temperature in which the surrounding air temperature needs to be cooled to reach 100 percent relative humidity.

It is the value that tells us how much moisture is in the atmosphere.

The closer the dew point is to the ambient air temperature, the more moisture there is in the atmosphere. Warmer air holds much more moisture than cooler air, but this can feel quite different depending on where you live and the time of year!

Dew points can never be higher than the air temperature. It can only be equal to (100 percent humidity) or less than the air temperature (<100 percent humidity).

Learn more with our Weather Explained video!

Weather & Radar editorial team
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