UV Index in Janesville, United States

Last updated: June 2, 2025

Understanding the UV Index in Janesville, United States, is crucial for safeguarding your skin health against the sun’s harmful rays. As this charming city experiences a Csb climate, awareness of UV levels helps you prevent sunburn and related skin issues, particularly during peak hours when the index can reach a blistering 12. With the potential for high UV exposure, especially between 11:00 AM and 1:00 PM, it’s essential to take proactive measures for your safety. Stay informed and enjoy the outdoors while protecting your skin from unnecessary damage!

Hourly UV Index in Janesville

Throughout the day, the UV Index displayed a dynamic pattern, peaking at an intense 12 around 1 PM. Starting off gently at 1 by 7 AM, it climbed steadily, reaching 9 by 11 AM, a clear sign to take precautions. As the sun approached its zenith, the index swelled to its maximum at 12 PM, emphasizing the importance of sun safety. Following the midday peak, the index gradually decreased, dropping to 9 by 3 PM, then tapering off further to 2 by 6 PM and 1 by 7 PM. This data underscores the significance of shielding oneself from the sun's harmful rays during the day, especially when the UV Index is at its highest.

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	12	extreme	10 min
14:00	11	extreme	10 min
15:00	9	very high	15 min
16:00	6	high	25 min
17:00	4	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Janesville

Throughout the year, the UV Index experiences significant fluctuations, with high-risk months primarily occurring from March to September. During these months, particularly in May, June, July, and August, the UV Index reaches extreme levels (11-12), requiring individuals to take extra precautions with an average burn time of just 10 minutes. In contrast, the months of January, February, November, and December have a moderate Index (3-4), allowing for safer sun exposure with burn times up to 30 minutes. Visitors and residents are advised to be vigilant during the peak months, utilizing sunscreen, wearing protective clothing, and seeking shade to mitigate the risk of UV-related harm.

Monthly Maximum UV Index for Janesville, United States

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

The table above highlights how UV exposure in Janesville 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.

Janesville'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
Janesville	4	5	8	9	11	12	11	11	9	7	4	3
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5