UV Index in Union City, United States

Last updated: June 2, 2025

Understanding the UV Index is crucial for residents of Union City, United States, where sun exposure can significantly impact skin health. Monitoring UV levels not only helps in preventing sunburns but also plays a vital role in reducing the risk of skin cancer over time. With a Cfa climate, Union City experiences warm summers and moderate UV exposure, peaking around midday with indices reaching up to 11. Being aware of these fluctuations allows residents to take proactive measures for sun protection and enjoy the outdoors safely.

Hourly UV Index in Union City

The UV Index for the day reveals a dynamic shift in sun exposure, starting off low in the early morning hours with values of 1 at both 7:00 and 8:00. As the sun climbs higher, the index ramps up, peaking at an intense 11 between 13:00 and 14:00—a clear signal for sun safety measures. This period of maximum intensity comes after a sharp rise from 3 at 9:00 to a notable 7 at 11:00. The afternoon provides a gradual decline, with levels falling to 9 by 15:00, then tapering off to 3 by 18:00 before returning to a safe 1 at 19:00. It's a solid reminder to stay protected during peak hours!

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
09:003moderate30 min
10:005moderate30 min
11:007high25 min
12:0010very high15 min
13:0011extreme10 min
14:0011extreme10 min
15:009very high15 min
16:007high25 min
17:005moderate30 min
18:003moderate30 min
19:001low45 min

Monthly UV Index Trends in Union City

Throughout the year, UV Index levels exhibit notable seasonal changes. The months of April to July are particularly high-risk, with an extreme UV Index of 11, leading to a burn time of just 10 minutes. This period necessitates extra caution, with visitors and residents advised to wear protective clothing, hats, and sunscreen. As summer wanes, the UV Index gradually decreases but remains very high in August to October, with burn times ranging from 15 to 25 minutes. January and December present the lowest UV levels, categorized as moderate, where burn times extend to 30 minutes. It is essential for everyone to remain vigilant with sun protection, especially during the high-risk months.

Monthly Maximum UV Index for Union City, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Union City. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec47811111111109864
Data source: Statistical UV Index data for Union 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 Union City UV Index with Other United States Cities

The table above highlights how UV exposure in Union 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.
Union 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
Union City47811111111109864
Houston UVI589111112121110975