UV Index in San Antonio, Puerto Rico

Last updated: June 2, 2025

Staying informed about the UV Index in San Antonio, Puerto Rico is crucial for safeguarding your skin and overall health, especially in a climate that sees plenty of sunny days. Understanding the varying levels of UV exposure throughout the day helps in sunburn prevention and promotes healthier skin over time. With UV Index values soaring as high as 13 during midday, it’s essential to be aware of the risks associated with sun exposure in this tropical region. By knowing when to seek shade and apply sunscreen, you can enjoy San Antonio's beautiful weather while minimizing the threats of harmful UV rays.

Hourly UV Index in San Antonio

The UV Index begins at a mild level of 1 at 07:00, but as the sun climbs higher, it swiftly escalates. By 10:00, it peaks at a critical 9, reaching a maximum of 13 at 12:00, indicating that protective measures are essential. After noon, the index gradually declines, tapering to 7 by 15:00, before dipping to a 2 by 17:00, and finally settling at 0 by 19:00 as the sun sets. This data highlights the importance of sun safety during the hours when UV exposure is at its highest, particularly around midday.

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	3	moderate	30 min
09:00	5	moderate	30 min
10:00	9	very high	15 min
11:00	11	extreme	10 min
12:00	13	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 Antonio

Throughout the year, UV Index levels vary significantly, with the highest readings occurring from February to October. During this period, the UV Index remains predominantly in the extreme category, peaking at 14 in May and remaining consistently high at 13 from June to September. The months at highest risk for UV exposure are February to October, where the burn time is reduced to just 10 minutes. January, November, and December see a slight decrease in risk, with UV Index levels categorized as very high and a longer burn time of 15 minutes. Visitors and residents are advised to take extra precautions during these peak months by wearing protective clothing, applying broad-spectrum sunscreen frequently, and seeking shade during peak hours to minimize skin damage.

Monthly Maximum UV Index for San Antonio, Puerto Rico

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in San Antonio. 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 Antonio, 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 Antonio UV Index with Other Puerto Rico Cities

The table above highlights how UV exposure in San Antonio 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 Antonio'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
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
San Juan UVI	9	11	13	13	14	13	12	13	13	12	9	8
San Antonio	9	11	13	13	14	13	13	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