UV Index in Union, United States

Last updated: June 2, 2025

Understanding the UV Index in Union, United States is crucial for protecting your skin and overall health. Given the area's Cfa climate, residents often face varying UV exposure risks, especially during peak hours when levels can soar to a maximum of 11 around noon. Recognizing UV levels is essential to prevent sunburn and long-term skin damage, making it important to stay informed. By being aware of the UV Index daily, you can enjoy the beautiful outdoors while safeguarding your skin from harmful ultraviolet rays.

Hourly UV Index in Union

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

Throughout the year, the UV Index displays notable seasonal fluctuations, particularly increasing from January to August. The highest risk occurs during the spring and summer months, with April through August recording an extreme UV Index of 11, necessitating a burn time as short as 10 minutes. March and September follow closely with very high indices of 8 and 10, respectively. Hence, visitors and residents are advised to take precautions during February to October, particularly in the peak summer months. Sunscreen application, protective clothing, and seeking shade during peak hours are essential for minimizing harmful UV exposure and preventing sunburn. In contrast, the winter months of January, November, and December see lower UV levels, offering a respite, albeit still warranting moderate protection.

Monthly Maximum UV Index for Union, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Union. 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, 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 UV Index with Other United States Cities

The table above highlights how UV exposure in Union 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'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	4	7	8	11	11	11	11	11	10	8	6	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5