UV Index in San Juan, United States

Last updated: June 2, 2025

In San Juan, United States, being aware of the UV Index is crucial for maintaining healthy skin and preventing sunburn, especially given the region's temperate climate. With UV levels reaching their peak at 12 during midday, understanding these fluctuations helps residents and visitors make informed choices about sun protection. As you enjoy the beautiful outdoor activities San Juan has to offer, staying mindful of UV exposure not only safeguards your skin health but also enhances your overall well-being. So, whether you're lounging on the beach or hiking in the nearby hills, keep an eye on the UV Index to enjoy the sun safely!

Hourly UV Index in San Juan

Throughout the day, the UV Index experiences a dynamic shift, peaking at an impressive 13 between 1 PM and 2 PM, indicating a high risk of harm from unprotected sun exposure. The morning starts gently, with a UV Index of 1 at 7 AM, gradually rising to 4 by 9 AM. As the sun inches higher, the intensity increases sharply, reaching 10 by 11 AM and soaring to 12 by noon. Post-peak, the index begins to decline, dropping to 10 at 3 PM, before settling back to a mild 2 by 6 PM. This clear progression emphasizes the importance of sun protection during the midday hours when the UV Index is at its highest. Enjoy the sunshine, but remember to stay safe! ☀️

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
10:007high25 min
11:0010very high15 min
12:0012extreme10 min
13:0013extreme10 min
14:0012extreme10 min
15:0010very high15 min
16:007high25 min
17:004moderate30 min
18:002low45 min
19:001low45 min

Monthly UV Index Trends in San Juan

Throughout the year, UV Index levels exhibit significant seasonal changes, with high-risk months primarily falling between February and September. The index peaks in June and July at 13, categorized as extreme, indicating that unprotected skin can burn in as little as 10 minutes. March, April, and May also see very high to extreme levels, with UV indices of 10 to 12. Conversely, January, November, and December present lower risks with moderate to high levels, allowing for longer exposure times. Residents and visitors should take precautions during high-risk months by wearing sunscreen, protective clothing, and seeking shade, especially during peak sun hours to minimize the risk of skin damage.

Monthly Maximum UV Index for San Juan, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in San Juan. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec5810111213131211864
Data source: Statistical UV Index data for San Juan, 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 San Juan UV Index with Other United States Cities

The table above highlights how UV exposure in San Juan 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.
San Juan's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
 JanFebMarAprMayJunJulAugSepOctNovDec
Chicago UVI34689101098642
Brooklyn UVI35681010998642
New York City UVI35681010998642
Los Angeles UVI46891011111010754
Houston UVI589111112121110975
San Juan5810111213131211864