UV Index in Charlestown, United States

Last updated: June 2, 2025

Understanding the UV Index in Charlestown, United States, is essential for protecting your skin and overall health. With UV levels peaking at 9 during midday hours, awareness can help you prevent sunburn and reduce long-term skin damage. Charlestown's Cfa climate brings ample sunshine, making it crucial to pay attention to daily UV exposure risks. By staying informed about UV indices, you can enjoy the sun safely, keeping your skin healthy while savoring everything this vibrant community has to offer.

Hourly UV Index in Charlestown

As the day unfolds, the UV Index experiences a dramatic rise, peaking at an intense 10 around 1 PM, signaling the highest level of harmful UV radiation. Early morning hours start gently, with a maximum of 1 at 7 AM, gradually increasing to a moderate 4 by 9 AM. The ascent continues steadily, reaching a notable 8 between 11 AM and 12 PM before soaring to its zenith. After this peak, the index begins to wane, declining to 5 by 4 PM and dropping further to a safe 1 by 7 PM. It’s vital to stay protected during the peak hours of 11 AM to 3 PM to enjoy the sunshine without compromising 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	9	very high	15 min
13:00	10	very high	15 min
14:00	9	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	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Charlestown

Throughout the year, UV exposure changes significantly, with high-risk months identified from April to September, when the UV Index reaches notably high levels of 9 to 10. During these months, burn times are critically reduced to just 15 minutes, requiring extra caution. March marks the transition to higher UV levels, with an index of 7 and a 25-minute burn time, while January and February begin with a moderate UV Index of 3 to 5 and longer burn times of 30 minutes. As we move into the fall, UV exposure decreases, dropping to 4 in November and 3 in December. Visitors and residents are advised to protect their skin by wearing sunscreen, protective clothing, and seeking shade, particularly during high-risk months, to minimize the risk of UV-related skin damage.

Monthly Maximum UV Index for Charlestown, United States

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

The table above highlights how UV exposure in Charlestown 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.

Charlestown'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
Charlestown	3	5	7	9	10	10	10	9	8	6	4	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