UV Index in Thornton, United States

Last updated: May 3, 2025

Understanding the UV Index in Thornton, United States, is essential for safeguarding your skin against harmful ultraviolet radiation. As UV levels can rise significantly, particularly during peak hours in the sun-filled climate of Thornton, being aware of these levels can help you take preventive measures against sunburn and long-term skin health issues. With maximum UV indices reaching as high as 9 in the early afternoon, residents must stay informed about their daily exposure risks to enjoy the outdoors safely and protect their skin year-round.

Hourly UV Index in Thornton

As the sun rises, the UV Index gradually climbs, starting at a mild 1 at 07:00. By 08:00, it nudges up to 2, signaling a gentle start to the day. The real intensity kicks in at 09:00, reaching 4, and peaks impressively at 12:00 with a high of 9. The UV levels remain strong throughout the afternoon, holding at 9 until 13:00, before tapering off slightly to 8 at 14:00. By 15:00, it decreases to 7, and as the sun begins its descent, the index drops dramatically, hitting 4 by 16:00 and further declining to a safe 1 by 18:00 and 19:00. Staying sun-safe during the peak hours between 10:00 and 14:00 is essential to protect your skin from harmful UV 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	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	4	moderate	30 min
17:00	3	moderate	30 min
18:00	1	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