UV Index in Lewiston, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for residents of Lewiston, United States, especially given its unique climate. With summer temperatures climbing and the sun's rays becoming more intense, being aware of UV levels can help you prevent painful sunburns and protect your long-term skin health. During the midday hours, the UV Index can peak as high as 9, which poses a significant risk for skin damage. In Lewiston's Csb climate, it's essential to stay informed and take precautions against harmful UV exposure, ensuring that outdoor activities remain enjoyable and safe.

Hourly UV Index in Lewiston

The UV Index for today presents an intriguing journey through the hours. It starts off gently at 1 at 07:00, but as the morning progresses, it climbs swiftly to 2 by 08:00 and reaches a moderate 4 at 09:00. The sun intensifies its rays further, peaking at a robust 9 between 12:00 and 13:00—a reminder to take precautions against harmful UV exposure. Following this peak, the index gradually descends, dipping to 6 at 15:00, and mellowing down to 1 by 18:00. This pattern highlights the importance of seeking shade or applying sunscreen during the midday hours when UV radiation is most potent.

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.
TimeUVICategoryTime to Burn
07:001low45 min
08:002low45 min
09:004moderate30 min
10:006high25 min
11:008very high15 min
12:009very high15 min
13:009very high15 min
14:008very high15 min
15:006high25 min
16:004moderate30 min
17:003moderate30 min
18:001low45 min
19:001low45 min

Monthly UV Index Trends in Lewiston

Throughout the year, the UV Index shows significant seasonal variations, indicating changes in the sun's intensity. January and December have the lowest UV levels (2), categorized as low exposure, allowing for longer burn times of up to 45 minutes. However, as we transition into February and March, the index rises to moderate (4) and high (6) categories, respectively, with reduced burn times of 30 and 25 minutes. The most critical months for sun exposure are from April to August, where the UV Index reaches its peak at 10 during June and July, classified as very high exposure with a rapid burn time of just 15 minutes. The UV levels then gradually decrease in September to high (7) and back to moderate levels in October and November. Visitors and residents are advised to take extra precautions during the high-risk months of April to August, by wearing protective clothing, applying sunscreen frequently, and minimizing sun exposure during peak hours.

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.
JanFebMarAprMayJunJulAugSepOctNovDec24689101097532
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.
 JanFebMarAprMayJunJulAugSepOctNovDec
Lewiston24689101097532
Chicago UVI34689101098642
Brooklyn UVI35681010998642
New York City UVI35681010998642
Los Angeles UVI46891011111010754
Houston UVI589111112121110975