relative humidity

noun

: the ratio of the amount of water vapor actually present in the air to the greatest amount possible at the same temperature

Examples of relative humidity in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Afternoon relative humidity values will fall into the 15-25% range by Wednesday. Ca Wildfire Bot, Sacbee.com, 15 Sep. 2025 The region was forecast to see hot conditions, including low relative humidities, an unstable air mass, and temperatures reaching triple digits, according to the Central Oregon Fire Information. Thao Nguyen, USA Today, 24 Aug. 2025 Gusty winds up to 25 mph, relative humidities as low as 9% and hot temperatures could fuel rapid fire growth, according to the warning. Lauren Penington, Denver Post, 14 Aug. 2025 What To Know The NWS on Monday implemented a red-flag warning across parts of Colorado, Idaho, Nevada, Utah and Wyoming amid concerns that strong winds, low relative humidity and warm temperatures could lead to fires across those states. Andrew Stanton, MSNBC Newsweek, 4 Aug. 2025 See All Example Sentences for relative humidity

Word History

First Known Use

1819, in the meaning defined above

Time Traveler
The first known use of relative humidity was in 1819

Browse Nearby Words

Cite this Entry

“Relative humidity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/relative%20humidity. Accessed 16 Sep. 2025.

Kids Definition

relative humidity

noun
: the amount of water vapor actually present in the air compared to the greatest amount possible at the same temperature

Medical Definition

relative humidity

noun
: the ratio of the amount of water vapor actually present in the air to the greatest amount possible at the same temperature compare absolute humidity

More from Merriam-Webster on relative humidity

Last Updated: - Updated example sentences
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