UV Index in Union City, United States

Last updated: June 2, 2025

Understanding the UV Index is crucial for residents of Union City, as awareness of ultraviolet radiation levels can significantly impact skin health and help prevent painful sunburns. With a temperate Cfa climate, Union City experiences varying UV exposure throughout the day, peaking at a concerning level of 11 around noon. By tracking these UV levels, locals can take proactive measures to protect themselves from harmful effects, ensuring their time outdoors is both enjoyable and safe. Stay informed and safeguard your skin by keeping an eye on the UV Index!

Hourly UV Index in Union City

At dawn, the UV Index starts at a gentle 1 by 07:00, indicating minimal exposure risk. As the sun climbs higher, the intensity rises sharply, reaching a maximum of 11 between 12:00 and 13:00—a time when protective measures are crucial. The peak UV Index highlights the importance of sun safety, as conditions can be particularly harsh. The afternoon sees a gradual decline, dipping to 8 by 15:00 and further decreasing to 3 by 17:00. As evening approaches, the index wanes to a mellow 1 by 19:00, suggesting a return to safer exposure levels. Keep in mind that tracking the UV Index throughout the day can help protect your skin from harmful rays!

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	2	low	45 min
09:00	4	moderate	30 min
10:00	7	high	25 min
11:00	9	very high	15 min
12:00	11	extreme	10 min
13:00	11	extreme	10 min
14:00	10	very high	15 min
15:00	8	very high	15 min
16:00	6	high	25 min
17:00	3	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, the UV Index varies significantly, with high-risk months occurring primarily from April to August, where the index reaches extreme levels of 10-11. During these months, the recommended burn time drastically decreases, dropping to as low as 10 minutes of unprotected sun exposure. Visitors and residents are advised to take extra precautions during these high UV Index periods by wearing protective clothing, applying sunscreen with a high SPF, and seeking shade during peak hours (10 AM to 4 PM). As the UV Index returns to moderate levels in January, November, and December, the risk of skin damage decreases, but sun safety remains essential year-round.

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
Union City	3	6	7	10	11	11	11	10	9	7	5	3
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5