UV Index in Boulder City, United States

Last updated: June 2, 2025

In Boulder City, United States, understanding the UV Index is crucial for maintaining healthy skin and preventing sunburn. With the region's arid BWh climate, residents and visitors alike are exposed to increased UV levels, especially during the peak hours of 10 AM to 2 PM, when the index soars to a maximum of 12. Awareness of UV levels not only helps individuals take protective measures but also promotes long-term skin health. As you navigate Boulder City's sunny days, staying informed about the UV Index can make all the difference in enjoying the outdoors safely.

Hourly UV Index in Boulder City

The UV Index climbs steadily throughout the morning, peaking at 12 around 1:00 PM, signaling a strong potential for skin damage without protection. Starting from a low of 1 at 7:00 AM, the index escalates, reaching a moderate 8 by 10:00 AM. As the sun hits its zenith, the index then soars to an impressive 11 at noon, before slightly dipping to 10 by 2:00 PM. By late afternoon, the index begins to decline, dropping to 5 by 4:00 PM, and tapering off to 3 by 5:00 PM, with the evening returning to a gentle 1. It's essential to stay covered and protected during those peak hours when UV exposure is at its highest!

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
08:003moderate30 min
09:005moderate30 min
10:008very high15 min
11:0010very high15 min
12:0011extreme10 min
13:0012extreme10 min
14:0010very high15 min
15:008very high15 min
16:005moderate30 min
17:003moderate30 min
18:001low45 min
19:001low45 min

Monthly UV Index Trends in Boulder 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 Boulder City, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Boulder City. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec46810111212119753
Data source: Statistical UV Index data for Boulder 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 Boulder City UV Index with Other United States Cities

The table above highlights how UV exposure in Boulder 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.
Boulder 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
Boulder City468101112121110753
Houston UVI589111112121110975