UV Index in San Francisco, Mexico

Last updated: June 2, 2025

Understanding the UV Index is crucial for residents and visitors in San Francisco, Mexico, where sun exposure can lead to serious skin health issues. By keeping an eye on UV levels, you can effectively prevent sunburn and protect your skin from long-term damage. San Francisco's diverse climate, often influenced by its geographical features, presents unique UV exposure risks, particularly during midday when the index peaks at 13. Awareness of these daily fluctuations not only safeguards your health but also enhances your overall enjoyment of San Francisco's beautiful outdoor attractions.

Hourly UV Index in San Francisco

The UV Index throughout the day follows a striking trend, starting from a minimum of 0 at 7:00 AM and gradually climbing as the sun rises. By 10:00 AM, it reaches a moderate 4, but the real intensity kicks in between 12:00 PM and 2:00 PM, peaking at an alarming 13 at 2:00 PM. This indicates that sun protection is crucial during these hours, as the UV rays are at their strongest. As the afternoon progresses, the index begins to dip, dropping to 10 at 4:00 PM and further to 6 at 5:00 PM, before cooling off to 3 by 6:00 PM and finally settling at a safe 1 by 7:00 PM. For anyone planning outdoor activities, understanding this UV Index pattern is essential for enjoying the sun wisely and 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.
TimeUVICategoryTime to Burn
07:000low45 min
08:001low45 min
09:002low45 min
10:004moderate30 min
11:006high25 min
12:0010very high15 min
13:0012extreme10 min
14:0013extreme10 min
15:0012extreme10 min
16:0010very high15 min
17:006high25 min
18:003moderate30 min
19:001low45 min

Monthly UV Index Trends in San Francisco

The UV Index exhibits significant seasonal variation, with the highest levels occurring from March to October, where exposure categories reach extreme status. March through August sees consistently high UV Index ratings of 12-13, resulting in a minimal burn time of just 10 minutes. Visitors and residents should be particularly cautious during these months, as the risk of sunburn is substantial. January and February also pose a risk with UV Index values near 10, categorized as very high, leading to a burn time of 15 minutes. As the seasons transition into November and December, the UV Index drops, but care should still be exercised. November has a UV Index of 9 (very high) with a burn time of 15 minutes, and December sees a further decrease to 7 (high), allowing for a slightly longer burn time of 25 minutes. To ensure safety, it is advisable to wear sunscreen, seek shade, and wear protective clothing during the high-risk months, especially from March to October when sun exposure can lead to serious skin damage in a short amount of time.

Monthly Maximum UV Index for San Francisco, Mexico

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in San Francisco. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec810121313131213121197
Data source: Statistical UV Index data for San Francisco, 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 Francisco UV Index with Other Mexico Cities

The table above highlights how UV exposure in San Francisco compares to other major locations across Mexico. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.
San Francisco's solar exposure compared to other cities in Mexico. Generated using Copernicus Atmosphere Monitoring Service information.
 JanFebMarAprMayJunJulAugSepOctNovDec
San Francisco810121313131213121197
Guadalajara UVI911141414131313131298
Iztapalapa UVI10121415141414141412108
Ecatepec de Morelos UVI10121415151414131412108
Mexico City UVI10121415151414131412108
Puebla UVI10121415151515141413109