UV Index in San Jose, Costa Rica

Last updated: May 3, 2025

In San Jose, Costa Rica, staying informed about the UV Index is crucial for protecting your skin and maintaining overall health. The UV Index measures the strength of ultraviolet radiation from the sun, highlighting the risk of sunburn and long-term skin damage. With a tropical climate characterized by intense sunlight, understanding the daily UV levels—especially during peak hours from 10 AM to 2 PM, when the index can reach a staggering 14—is vital for both residents and visitors. By being aware of these risks, you can take proactive measures to safeguard your skin and enjoy the beautiful Costa Rican sunshine safely.

Hourly UV Index in San Jose

At dawn, the UV Index begins at a gentle 2 at 7:00 AM, gradually climbing to a peak of 14 by 11:00 AM and 12:00 PM. This midday intensity signals a crucial time for sun safety, as the index emphasizes the need for protection against harmful rays. As the afternoon progresses, the UV levels decrease, dropping to 5 by 3:00 PM and falling further to 1 by 5:00 PM. By 6:00 PM, the index gracefully settles at 0, marking the end of a sun-soaked day. Stay mindful of these UV changes to enjoy the sun safely!

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	2	low	45 min
08:00	5	moderate	30 min
09:00	9	very high	15 min
10:00	12	extreme	10 min
11:00	14	extreme	10 min
12:00	14	extreme	10 min
13:00	12	extreme	10 min
14:00	8	very high	15 min
15:00	5	moderate	30 min
16:00	2	low	45 min
17:00	1	low	45 min
18:00	0	low	45 min
19:00	0	low	45 min

Monthly UV Index Trends in San Jose

Throughout the year, UV radiation levels remain notably high, with an extreme UV Index ranging from 11 to 16. The months of January to April exhibit the highest UV exposure, peaking in April at an index of 16. This trend remains consistent until October, when a slight decrease occurs, yet October still holds a significant index of 15. November and December show a slight reduction in UV levels, but caution is still advised as the exposure remains extreme. Visitors and residents should be particularly vigilant from January to October, during which time burn time is limited to just 10 minutes. Protective measures such as wearing sunscreen, hats, and sunglasses are essential, especially during these high-risk months to prevent sunburn and long-term skin damage.

Monthly Maximum UV Index for San Jose, Costa Rica

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in San Jose. 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 Jose, 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 Jose UV Index with Other Costa Rica Cities

The table above highlights how UV exposure in San Jose compares to other major locations across Costa Rica. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.

San Jose's solar exposure compared to other cities in Costa Rica. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Limon UVI	12	13	14	15	14	13	13	13	13	14	11	10
Liberia UVI	11	13	14	14	14	14	14	13	13	13	11	10
Alajuela UVI	12	13	15	15	14	14	14	13	13	14	12	10
San Jose	12	14	15	16	14	14	14	14	14	15	12	11
Paraiso UVI	13	14	16	16	15	15	15	14	14	15	12	11