UV Index in San Juan, Puerto Rico

Last updated: July 2, 2025

Understanding the UV Index in San Juan, Puerto Rico, is crucial for anyone enjoying the sun-soaked beaches or vibrant outdoor lifestyle here. With an average UV Index that can reach as high as 12, awareness of UV levels is essential to prevent sunburn and protect your skin health. The tropical climate, characterized by its warm temperatures and strong sun, means that residents and visitors alike face increased exposure risks, particularly during peak hours. By staying informed about the UV Index, you can make safer choices for your skin and enjoy all that San Juan has to offer while minimizing harmful UV effects.

Hourly UV Index in San Juan

The UV Index today presents a notable ascent as the sun reaches its zenith. Starting from a modest 1 at 07:00, it gradually climbs to 2 by 08:00. The real surge begins by 09:00, where it hits 5, and peaks at a striking 12 between 12:00 and 13:00. This intense period signals a vital awareness for sun protection! As the day progresses, the index drops steadily, descending to 10 at 14:00 before tapering off to 7 at 15:00, and dwindling down to 1 by 18:00 and flatlining at 0 by 19:00. Be mindful of peak hours for sun exposure, especially during the late morning to early afternoon when UV intensity 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	5	moderate	30 min
10:00	8	very high	15 min
11:00	11	extreme	10 min
12:00	12	extreme	10 min
13:00	12	extreme	10 min
14:00	10	very high	15 min
15:00	7	high	25 min
16:00	4	moderate	30 min
17:00	2	low	45 min
18:00	1	low	45 min
19:00	0	low	45 min

Monthly UV Index Trends in San Juan

The UV Index shows significant seasonal variation, peaking during the months of March to October, when levels reach between 12 and 14, categorizing them as extreme with a burn time of just 10 minutes. The highest risk months are April, May, and August, where the UV Index reaches 13 to 14. In contrast, January, February, and November still present very high exposure risks with less urgency, allowing for burn times of 15 minutes. Visitors and residents are strongly advised to take protective measures during the high UV months by wearing sunscreen, protective clothing, and sunglasses, and to limit sun exposure, especially during midday hours when the sun's rays are strongest.

Monthly Maximum UV Index for San Juan, Puerto Rico

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.

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 Puerto Rico Cities

The table above highlights how UV exposure in San Juan compares to other major locations across Puerto Rico. 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 Puerto Rico. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
San Juan	9	11	13	13	14	13	12	13	13	12	9	8
Caguas UVI	9	11	13	13	14	13	12	13	13	12	9	8
Carolina UVI	9	11	13	13	14	13	12	13	13	12	9	8
Bayamon UVI	9	11	13	13	14	13	13	13	13	12	9	8
Ponce UVI	9	11	13	14	14	13	13	13	14	12	10	9