UV Index in Union City, United States

Last updated: June 2, 2025

Understanding the UV Index in Union City is essential for protecting your skin and overall health. With a climate classified as Dfb, Union City's residents face varying UV exposure levels throughout the day, especially peaking around noon when the Index hits 10. Knowing these levels helps prevent sunburn and reduces the long-term risks of skin damage, making it vital to stay informed. While the mornings start with milder readings, the risk escalates sharply by late morning, underscoring the importance of UV awareness for safe sun practices in this vibrant community.

Hourly UV Index in Union City

The UV index begins its ascent at 07:00, starting at a gentle 1, then climbs gradually through the morning. By 10:00, it reaches a moderate 5, but from 11:00 onwards, the sun's intensity becomes pronounced, peaking at an impressive 10 between 13:00 and 14:00. After this zenith, the index dips to 8 at 15:00 and continues its decline, settling back to 2 by 18:00. As the day winds down into the evening, the UV index drops to a low 1 by 19:00, signaling a return to safer sun exposure levels. Enjoy the sunshine while staying protected during the high points!

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	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	10	very high	15 min
14:00	10	very high	15 min
15:00	8	very high	15 min
16:00	6	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 exposure varies significantly, peaking in the late spring and summer months. April to August represent the high-risk period, with UV Index values reaching 10; indicating a very high exposure category and a burn time as short as 15 minutes. Visitors and residents should exercise caution and take protective measures, such as wearing sunscreen and protective clothing during these months. In contrast, January and December have moderate and low UV levels, respectively, with longer burn times of 30 to 45 minutes. Action is still advisable during these months, but the intensity is notably lower, allowing for safer outdoor activities. Overall, awareness of seasonal UV changes is essential for protecting skin health 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	5	6	8	10	10	10	9	8	6	4	2
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