UV Index in Johnstown, United States

Last updated: July 2, 2025

Understanding the UV Index is essential for residents of Johnstown, United States, where the altitude and BSk climate combine to create unique sun exposure challenges. Being aware of UV levels throughout the day can help prevent painful sunburns and protect long-term skin health. With peak levels reaching a maximum of 12 around midday, it’s crucial to know when to seek shade or apply sunscreen. As Johnstown basks in sunshine, equipping yourself with UV Index knowledge can make a significant difference in keeping your skin safe and healthy under the sun.

Hourly UV Index in Johnstown

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 Johnstown

Throughout the year, UV levels exhibit significant seasonal variations, with high-risk months occurring from March to August, when the UV Index consistently reaches very high to extreme levels. April and May display peak values of 11, while June and July escalate to 12, indicating a critical need for sun protection during these times. Visitors and residents should exercise caution, especially during peak sunlight hours, by wearing protective clothing, applying broad-spectrum sunscreen, and seeking shade to minimize the risk of skin damage. As autumn approaches, the UV Index gradually decreases, returning to moderate levels in November and December, providing a more comfortable sun exposure environment.

Monthly Maximum UV Index for Johnstown, United States

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

The table above highlights how UV exposure in Johnstown 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.

Johnstown'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
Johnstown	4	6	8	11	11	12	12	11	9	6	4	3
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5