UV Index in Sao Joao, Portugal

Last updated: May 3, 2025

In Sao Joao, Portugal, awareness of the UV Index is crucial for maintaining skin health and preventing sunburn, especially given the region’s Mediterranean climate characterized by warm summers and variable overcast days. Understanding UV levels helps residents and visitors alike take the necessary precautions to protect their skin during peak hours of exposure, particularly between 11 AM and 2 PM when the index can soar to 10. With a typical daily pattern showing significant variation from 1 in the early morning to 9 in the early afternoon, being informed about UV risks is essential for enjoying the sunny weather safely.

Hourly UV Index in Sao Joao

The UV Index throughout the day presents a clear narrative of rising intensity, peaking in the afternoon. Starting at 1 by 07:00, the UV levels gradually ascend, reaching 5 by 10:00. By 11:00, the index climbs to 7, and it soars to a striking 10 at 13:00—the optimal time for sun precautions. The intensity slightly wanes thereafter, dropping to 9 at 14:00 and continuing down to 4 by 17:00. As evening approaches, the UV Index dwindles to 1 by 19:00, signaling a return to safer levels. This data underscores the importance of sun safety measures during peak hours, particularly between 11:00 and 14:00.

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	1	low	45 min
09:00	3	moderate	30 min
10:00	5	moderate	30 min
11:00	7	high	25 min
12:00	9	very high	15 min
13:00	10	very high	15 min
14:00	9	very high	15 min
15:00	8	very high	15 min
16:00	6	high	25 min
17:00	4	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Sao Joao

As the seasons change, so do the UV levels, which significantly impact skin safety for both visitors and residents. The UV Index starts low in January (2) and December (2), indicating a low risk for sunburn. However, as we move into the spring and summer months, particularly from March (6) to August (9), the risk escalates, with April (8) and the peak in June (11) classified as extreme. The high-risk months are primarily from April through August, where burn times are notably short, especially in June, with only 10 minutes until skin damage occurs. It is crucial for individuals during these months to take necessary precautions, such as wearing sunscreen, protective clothing, and limiting sun exposure, especially during peak hours. As fall approaches, the UV Index gradually decreases, but awareness remains essential for safe outdoor activities.

Monthly Maximum UV Index for Sao Joao, Portugal

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Sao Joao. 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 Sao Joao, 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 Sao Joao UV Index with Other Portugal Cities

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

Sao Joao's solar exposure compared to other cities in Portugal. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Braga UVI	2	4	6	8	9	11	10	9	8	6	4	2
Porto UVI	2	4	6	8	9	11	10	9	8	6	4	2
Sao Joao	2	4	6	8	9	11	10	9	8	6	4	2
Amadora UVI	3	5	6	9	10	11	10	9	8	6	4	3
Lisbon UVI	3	5	6	9	10	11	10	9	8	6	4	3
Setubal UVI	3	5	6	9	10	11	10	9	8	6	4	3