UV Index in Knoxville, United States

Last updated: July 2, 2025

In Knoxville, United States, being aware of the UV Index is crucial for protecting your skin and overall health. Understanding UV levels can help prevent sunburn and reduce the risk of long-term skin damage as the sun's rays can be intense, especially during the peak hours between 11 AM and 2 PM when the UV Index often soars to a high of 11. With a Cfa climate, Knoxville experiences warm summers that can elevate UV exposure risks, making it essential for residents and visitors alike to stay informed and take necessary precautions to safeguard their skin while enjoying the outdoors.

Hourly UV Index in Knoxville

The UV Index (UVI) paints a clear picture of sun intensity throughout the day. Beginning at 07:00, the index registers a low 1, making it a safe time for early risers. As the sun climbs higher, the numbers take a dramatic turn: by 11:00, the UVI jumps to 7, signaling increased sun exposure. The peak occurs between 12:00 and 14:00, where it reaches an intense 11, urging caution for outdoor activities. The intensity gradually wanes after this peak, dropping to 5 by 17:00 and returning to a mild 1 once again by 19:00. Whether planning your day or heading outdoors, it's crucial to stay sun-smart during those peak hours!

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	1	low	45 min
09:00	2	low	45 min
10:00	4	moderate	30 min
11:00	7	high	25 min
12:00	9	very high	15 min
13:00	11	extreme	10 min
14:00	11	extreme	10 min
15:00	9	very high	15 min
16:00	7	high	25 min
17:00	5	moderate	30 min
18:00	3	moderate	30 min
19:00	1	low	45 min

Monthly UV Index Trends in Knoxville

Throughout the year, UV exposure levels vary significantly, with high-risk months typically occurring from March to August when the UV Index reaches its peak at 11, categorized as extreme. March and April also feature very high levels, making these months crucial for sun safety awareness. Visitors and residents should be particularly cautious during this period, applying sunscreen regularly, wearing protective clothing, and seeking shade during peak hours. In contrast, the months of January, November, and December present a moderate UV Index of 3 to 5, allowing for more relaxed precautions, though it's still important to remain mindful of sun exposure. Always check local UV forecasts and adjust your sun safety practices accordingly to protect your skin year-round.

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	6	8	10	11	11	11	10	9	7	5	3
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