UV Index in Union City, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for residents of Union City, where sunny days can quickly escalate into potential risks for skin health. With the city's Cfa climate bringing warm, sunny weather, awareness of UV levels helps in the prevention of painful sunburns and long-term skin damage. On any given day, Union City can see UV Index peaks reaching up to 11, indicating a very high risk of harm from unprotected sun exposure. Being informed empowers you to take necessary precautions, enjoy outdoor activities safely, and protect your skin’s overall health.

Hourly UV Index in Union City

As the sun rises on this vibrant day, the UV Index begins its steady ascent. Starting at a mild 1 at 07:00, it quickly climbs to 3 by 09:00, signaling that it’s time to enjoy some outdoor activities with caution. By 10:00, the index reaches a moderate 5, but the real heat kicks in at 11:00, peaking at an intense 11 from 13:00 to 14:00. During this peak, sun protection is crucial, especially for those planning to be outdoors. As the afternoon progresses, the UV Index gently declines, dropping to 7 by 16:00 and tapering off to 4 by 17:00. As the sun sets, the index returns to 1 by 19:00, marking a gentle end to a day of vibrant sunlight.

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.
Time	UVI	Category	Time to Burn
07:00	1	low	45 min
08:00	1	low	45 min
09:00	3	moderate	30 min
10:00	5	moderate	30 min
11:00	7	high	25 min
12:00	9	very high	15 min
13:00	11	extreme	10 min
14:00	11	extreme	10 min
15:00	9	very high	15 min
16:00	7	high	25 min
17:00	4	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 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.

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.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Chicago UVI	3	4	6	8	9	10	10	9	8	6	4	2
Brooklyn UVI	3	5	6	8	10	10	9	9	8	6	4	2
New York City UVI	3	5	6	8	10	10	9	9	8	6	4	2
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Union City	4	7	8	11	11	11	11	10	9	8	6	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5