UV Index in Boise City, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for residents of Boise City, where the unique BSk climate brings bright sunlight and varying UV exposure throughout the day. The UV Index provides valuable insights into the intensity of ultraviolet radiation, helping you make informed choices to prevent sunburn and protect your skin health. With daily peaks around 11 between noon and 2 PM, it’s important to be mindful of outdoor activities and safeguard yourself against potential skin damage. Stay informed about UV levels to enjoy all that Boise has to offer while prioritizing your well-being under the sun!

Hourly UV Index in Boise City

The UV Index for the day showcases a significant rise in solar intensity as the sun climbs higher in the sky. Starting at a low of 1 at 07:00 and 08:00, the index escalates to 2 by 09:00. A marked increase occurs between 10:00 and 12:00, where it jumps to 4 and peaks at a striking 9 at noon. The afternoon witnesses even higher levels, reaching a maximum of 11 at both 13:00 and 14:00, signifying a critical time for sun protection. As the sun begins to set, the index gradually declines to 5 at 17:00, and eventually returns to a safe 1 by 19:00. It’s essential to take precautions during those peak hours to safeguard against harmful UV exposure!

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
TimeUVICategoryTime to Burn
07:001low45 min
08:001low45 min
09:002low45 min
10:004moderate30 min
11:007high25 min
12:009very high15 min
13:0011extreme10 min
14:0011extreme10 min
15:0010very high15 min
16:008very high15 min
17:005moderate30 min
18:003moderate30 min
19:001low45 min

Monthly UV Index Trends in Boise City

Throughout the year, the UV Index exhibits significant seasonal variations, peaking during the summer months of May to August, where it reaches extremes of 11 to 12. The highest risk occurs in May, June, and July, with burn times as short as 10 minutes under these conditions. March and April also present considerable UV exposure, categorized as very high, with burn times of just 15 minutes. Visitors and residents should exercise caution from late winter through summer, especially during these high-risk months, by seeking shade, wearing protective clothing, and applying broad-spectrum sunscreen regularly to minimize the risk of skin damage. As the season transitions into fall and winter, UV levels decrease, offering more moderate exposure from October to December.

Monthly Maximum UV Index for Boise City, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Boise City. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec468101112121110753
Data source: Statistical UV Index data for Boise City, based on information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

Compare Boise City UV Index with Other United States Cities

The table above highlights how UV exposure in Boise City compares to other major locations across United States. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.
Boise City's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
 JanFebMarAprMayJunJulAugSepOctNovDec
Chicago UVI34689101098642
Brooklyn UVI35681010998642
New York City UVI35681010998642
Los Angeles UVI46891011111010754
Boise City468101112121110753
Houston UVI589111112121110975