UV Index in Helena, United States

Last updated: August 1, 2025

Awareness of the UV Index is crucial for residents of Helena, United States. Understanding UV levels not only helps in sunburn prevention but also plays a key role in maintaining overall skin health. With Helena's climate characterized as Cfa, residents face varying UV exposure risks throughout the day, particularly peaking at midday when the index can soar to 11—a level that calls for serious sun protection measures. By staying informed about the UV Index, you can enjoy the beautiful Montana sunlight while safeguarding your skin from harmful effects.

Hourly UV Index in Helena

As the sun rises, the UV Index begins its gradual climb from 1 at 7:00 AM, indicating minimal risk. By 9:00 AM, it reaches 4, signaling a moderate UV level. The intensity peaks dramatically at 12:00 PM, hitting an impressive 11, categorized as very high, before peaking at 1:00 PM with a maximum of 12. This is the hour to take extra precautions! As the afternoon progresses, the index gradually declines to 9 by 3:00 PM and further to 6 by 4:00 PM. As evening approaches, the UV levels drop quickly, falling back to 3 at 5:00 PM and returning to a safe 1 by 7:00 PM. For a day full of sunshine, remember to stay protected during the peak UV 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	2	low	45 min
09:00	4	moderate	30 min
10:00	6	high	25 min
11:00	9	very high	15 min
12:00	11	extreme	10 min
13:00	11	extreme	10 min
14:00	10	very high	15 min
15:00	8	very high	15 min
16:00	5	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 Helena

Throughout the year, UV levels fluctuate, with high-risk months primarily falling between February and August. Notably, April to July feature an extreme UV Index of 11 to 12, necessitating precautions to limit sun exposure to just 10 minutes during peak hours. February and March present significant risks as well, with very high UV levels of 8 and 9, leading to burn times of only 15 minutes. To safeguard your skin, residents and visitors are advised to minimize exposure during peak sun hours, wear protective clothing, and use broad-spectrum sunscreen. As the year progresses, November and December offer lower UV levels, classified as high and moderate, respectively, allowing for longer safe exposure times of 25 to 30 minutes.

Monthly Maximum UV Index for Helena, United States

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

The table above highlights how UV exposure in Helena 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.

Helena'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
Helena	5	8	9	11	11	11	12	11	10	8	6	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5