UV Index in Knoxville, United States

Last updated: May 3, 2025

In Knoxville, United States, being aware of the UV Index is crucial for protecting your skin and overall health. Understanding UV levels can significantly reduce your risk of sunburn and long-term skin damage, especially as Knoxville experiences a humid continental climate that can lead to heightened UV exposure during peak hours. With daily UV Index values soaring as high as 10 around midday, it’s essential for residents and visitors alike to stay informed and take appropriate sun safety measures. By keeping an eye on the UV Index, you can enjoy the beauty of Knoxville while ensuring your skin remains healthy and protected.

Hourly UV Index in Knoxville

As the sun rises, the UV Index begins to climb steadily, starting at a mild 1 at 7:00 AM. By 9:00 AM, it picks up pace, reaching 4. The intensity peaks around midday, soaring to a maximum of 10 between 1:00 PM and 2:00 PM, indicating a high risk of harm from unprotected sun exposure. As the afternoon progresses, the index gradually declines, settling at 6 by 4:00 PM, and tapering down to 2 by 6:00 PM. As the day winds down, the UV levels drop to 1 by 7:00 PM, encouraging a return to safety as the sun sets. Be sure to protect your skin during the peak hours for a safe and enjoyable day outdoors!

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	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	3	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Knoxville

Throughout the year, UV exposure varies significantly, peaking during late spring and summer months. High-risk months for UV exposure are April through September, where the UV Index frequently reaches levels classified as very high; particularly notable are May, June, and July, when it consistently hits a maximum of 10. Visitors and residents are advised to take precautions during these months, with burn times dramatically reduced to as little as 15 minutes. In contrast, January, February, and November present moderate UV levels, and December has a low index, making sun safety measures less critical during these months. To protect against skin damage, it is essential to wear sunscreen, seek shade, and wear protective clothing, especially between peak months of April and September.

Monthly Maximum UV Index for Knoxville, United States

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

The table above highlights how UV exposure in Knoxville 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.

Knoxville'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
Knoxville	3	5	6	9	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