UV index

American  

noun

1. a measure, on a scale of 0 to 11, of the intensity of ultraviolet radiation from the sun at the sun's highest point on a particular day in a particular place, a higher number indicating greater exposure.

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UV index Scientific  

/ yo̅o̅′vē′ /

1. A scale ranging from 0 to 10, used to estimate the risk for sunburn in midday sunlight, with 0 indicating no risk and 10 indicating maximal risk. The UV index is effectively a rough measure of the amount of harmful ultraviolet radiation in the sunlight reaching the Earth's surface at a given location, given the time of year and current atmospheric conditions, expressed in terms of the risks that are associated with exposure to that amount of radiation.

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Example Sentences

See Examples For:

UV index

She also suggested prominently displaying the UV index widget on Yahoo Weather, after noting the growing attention to sun exposure across social media and within her teenage daughter’s friendship group.

From The Wall Street Journal ● Jun. 8, 2026

During summer in the UK, that UV index would typically be around 5-6 with a maximum of 8 only in exceptional circumstances.

From BBC ● May 22, 2026

The UV index was listed at 11, or extreme.

From Seattle Times ● Jun. 23, 2023

You should also avoid the sun’s harshest rays: If your phone’s weather app has a UV index, consult it, Holman says.

From Washington Post ● Apr. 16, 2023

“Measures eighty values—temperature, UV index, dew point, you name it.”

From "A Walk in the Woods" by Bill Bryson