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

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

BBC Weather presenter Matt Taylor said there were exceptionally high levels of UV radiation, which could reach nine on the UV index.

From BBC • Jun. 25, 2020

From there you'll see the current temperature, chances of precipitation, UV index, humidity, and visibility, along with a short-term weather reading, an hourly forecast and a daily glance, all by swiping on the touchpad remote.

From The Verge • Oct. 30, 2015

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

From "A Walk in the Woods" by Bill Bryson