UV Index in Lewiston, United States

Last updated: July 2, 2025

In Lewiston, United States, being aware of the UV Index is crucial for maintaining your skin health and preventing sunburn. With a humid continental climate (Dfa), Lewiston experiences significant UV exposure, especially during the summer months when the index can reach peaks of 10 around midday. Understanding these UV levels empowers residents and visitors alike to take necessary precautions, protecting themselves from harmful effects of UV radiation. Stay informed to enjoy the sun safely and keep your skin healthy!

Hourly UV Index in Lewiston

As the sun rises, the UV Index gradually climbs, beginning at a mild 1 at 7:00 AM. By 9:00 AM, it reaches 3, prompting early risers to consider sun protection. The intensity peaks at 1:00 PM with a maximum of 10, signaling the most hazardous conditions for unprotected skin. As the afternoon unfolds, the index dips from 9 at 2:00 PM to 6 by 4:00 PM, offering a brief respite. As the day winds down, the UV rays decrease, falling to 2 by 6:00 PM and returning to a safe 1 by 7:00 PM. Stay mindful of these fluctuations to enjoy the sun while safeguarding your skin!

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	3	moderate	30 min
10:00	5	moderate	30 min
11:00	7	high	25 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	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 Lewiston

Throughout the year, seasonal UV changes significantly impact exposure levels, with the highest UV Index recorded during the summer months. High-risk months include April through September, where the UV Index reaches very high levels of 8 to 10, leading to a burn time as short as 15 minutes. In contrast, January and December present lower UV levels, categorized as low, allowing for burn times of up to 45 minutes. Visitors and residents are strongly advised to take precautions during high-risk months by applying sunscreen, wearing protective clothing, and seeking shade during peak sunlight hours to minimize the risk of skin damage.

Monthly Maximum UV Index for Lewiston, United States

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

The table above highlights how UV exposure in Lewiston 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.

Lewiston'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
Lewiston	2	4	5	8	9	10	10	9	8	5	3	2
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
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5