UV Index in Waterloo, United States

Last updated: June 2, 2025

Understanding the UV Index is crucial for residents of Waterloo, United States, where the climate presents unique sun exposure challenges. As temperatures rise and summer approaches, knowing the UV levels can help you protect your skin from harmful rays, preventing sunburn and reducing the risk of long-term skin health issues. With Waterloo's Dfa climate, typical UV levels peak around noon, reaching a maximum of 11—a reminder to take precautions during those hours. Stay informed and bask safely in the sun!

Hourly UV Index in Waterloo

The UV Index throughout the day follows a predictable rise and fall, peaking at 11 around 1:00 PM. Starting at a modest 1 at 7:00 AM, it gradually escalates, reaching 10 by 12:00 PM, signaling the need for sun protection. As the afternoon progresses, the index dips from 11 to 8 by 3:00 PM, then declines further to 2 by 6:00 PM, and finally settles back at 1 by 7:00 PM. This data underscores the importance of taking precautions during the hours of peak UV exposure, particularly between 11:00 AM and 3:00 PM, when levels are highest and pose the greatest risk to skin health.

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	10	very high	15 min
13:00	11	extreme	10 min
14:00	10	very high	15 min
15:00	8	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 Waterloo

The UV Index demonstrates significant seasonal variation throughout the year, peaking during the summer months. Notably, June reaches an extreme UV Index of 11, with a burn time of just 10 minutes, making it the highest risk period. May and July also have very high levels, at 9 and 10 respectively, with a burn time of 15 minutes. The spring months see a steady increase, with April at 8 and a burn time of 15 minutes, while March escalates to a high level with a burn time of 25 minutes. By contrast, January, February, October, November, and December display a moderate UV Index, typically allowing for a burn time of 30 minutes. Accordingly, visitors and residents should exercise caution, especially from March through September, when UV levels are notably higher. Regular use of sunscreen, protective clothing, and limiting sun exposure during peak hours is recommended to safeguard against skin damage.

Monthly Maximum UV Index for Waterloo, United States

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

The table above highlights how UV exposure in Waterloo 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.

Waterloo'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
Waterloo	3	5	6	8	9	11	10	9	8	5	3	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