UV Index in San Isidro, Costa Rica

Last updated: July 2, 2025

In San Isidro, Costa Rica, being aware of the UV Index is crucial for maintaining skin health and preventing sunburn. With its tropical climate, residents and visitors alike need to understand the varying levels of UV radiation throughout the day, especially as they soar to a peak index of 14 between 11:00 AM and 12:00 PM. This awareness not only aids in protecting your skin but also enhances your overall enjoyment of outdoor activities. As the sun shines brightly on this beautiful region, paying close attention to UV levels can help mitigate risks associated with prolonged sun exposure and ensure a safer, more enjoyable experience under the Costa Rican sun.

Hourly UV Index in San Isidro

The UV Index peaks dramatically during the midday hours, illustrating the sun's intensity in compelling detail. Starting at a modest 2 by 07:00, it swiftly ascends as the day unfolds. By 08:00, it jumps to 5, and then reaches a significant 8 at 09:00. The sun is at its fiercest between 10:00 and 12:00, with the index soaring to 14, an indication to take extra precautions! As 13:00 rolls around, the UV level dips slightly to 12, only to further decrease to 9 by 14:00. Post-midday, the sun's strength wanes; it dramatically drops to 5 by 15:00 and decreases to 1 by 17:00, finally settling at 0 by 19:00. Such data highlights the importance of sun protection during the peak hours when the 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	2	low	45 min
08:00	5	moderate	30 min
09:00	8	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	9	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 Isidro

The UV Index experiences extremely high levels throughout most of the year, peaking at 15 from March to May. Residents and visitors should take extra caution during these high-risk months, particularly from January through April when the UV Index remains consistently above 12. Even in the summer months of June to September, the UV Index remains at 14, indicating a persistent risk for skin damage. It is advisable to protect your skin by wearing sunscreen, protective clothing, and seeking shade whenever possible, especially during peak sun hours. Remember that even on cloudy days, UV rays can still pose a risk, so stay vigilant year-round.

Monthly Maximum UV Index for San Isidro, Costa Rica

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

The table above highlights how UV exposure in San Isidro 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 Isidro'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 Isidro	12	14	15	15	15	14	14	14	14	14	12	11
San Jose UVI	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