UV Index in Thornton, United States

Last updated: July 2, 2025

In Thornton, United States, staying aware of the UV Index is crucial for protecting your skin and overall health. Understanding UV levels helps you take necessary precautions against sunburns and long-term skin damage, especially during peak hours when the index reaches its highest (up to 9). Thornton's Dfb climate brings a range of seasonal weather patterns, but the sun's intensity can still pose a risk on clear days. By monitoring the UV Index, you can enjoy outdoor activities while minimizing the potential harm from UV exposure.

Hourly UV Index in Thornton

The UV Index today presents a notable climb as the sun ascends, peaking at 9 around noon and early afternoon, signaling very high sun exposure risk. Starting gently at 1 by 7 AM, the index rises steadily, reaching 6 by 10 AM and then surging to its maximum of 9 between 12 PM and 1 PM. Early afternoon brings a slight decline to 8 at 2 PM, followed by a gradual decrease through the later hours, settling back to 1 by 7 PM. With this trajectory, it's crucial to take precautions during the peak hours of 11 AM to 1 PM, ensuring skin protection against harmful UV rays. Stay safe and enjoy the sun wisely!

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	6	high	25 min
11:00	8	very high	15 min
12:00	9	very high	15 min
13:00	9	very high	15 min
14:00	8	very high	15 min
15:00	7	high	25 min
16:00	5	moderate	30 min
17:00	3	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Thornton

Throughout the year, the UV Index exhibits significant seasonal variation, with the highest levels occurring in late spring and summer months. Notably, April to August are identified as high-risk months, where the UV Index peaks at 10 in June and remains at 9 in both July and August, indicating very high exposure and requiring a burn time of only 15 minutes. In contrast, the winter months of January, February, and December show lower UV levels, with a moderate index of 3 and 2 respectively, allowing for longer exposure times without severe risk of burns. Visitors and residents are advised to adopt protective measures during high-risk months, such as applying sunscreen, wearing protective clothing, and seeking shade, to minimize the risk of overexposure.

Monthly Maximum UV Index for Thornton, United States

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

The table above highlights how UV exposure in Thornton 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.

Thornton'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
Thornton	3	4	6	8	9	10	9	9	7	5	3	2
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
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5