Last updated: May 3, 2025
In San Francisco, Mexico, being aware of the UV Index is vital for maintaining healthy skin and preventing sunburn. Understanding UV levels empowers residents and visitors to take necessary precautions against harmful rays, especially during peak sun exposure hours. With a climate zone categorized as As, the area experiences diverse weather, resulting in fluctuating UV risks throughout the day. For instance, the UV Index peaks at 13 between 1 PM and 2 PM, highlighting the importance of vigilance to safeguard your skin against potential damage. Stay informed and enjoy the sun safely!
As the day unfolds, the UV Index rises steadily, beginning at a safe 0 at 07:00 and peaking dramatically. By 10:00, it escalates to 4, signaling the need for some sun protection. The intensity reaches 10 at 12:00, and then hits its maximum at 13:00 with a formidable 12. Right after, it slightly dips but remains high at 12 until 15:00. As the afternoon wanes, the UV Index begins to decline, dropping to 9 by 16:00, and continuing its descent to 1 by 19:00. This fluctuation highlights the importance of being sun-smart during peak hours, especially between 11:00 and 15:00, when the sun is at its strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 0 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 13 | extreme | 10 min |
| 15:00 | 12 | extreme | 10 min |
| 16:00 | 9 | very high | 15 min |
| 17:00 | 6 | high | 25 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
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.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| San Francisco | 8 | 10 | 12 | 13 | 13 | 13 | 12 | 13 | 12 | 11 | 9 | 7 |
| Guadalajara UVI | 9 | 11 | 14 | 14 | 14 | 13 | 13 | 13 | 13 | 12 | 9 | 8 |
| Iztapalapa UVI | 10 | 12 | 14 | 15 | 14 | 14 | 14 | 14 | 14 | 12 | 10 | 8 |
| Ecatepec de Morelos UVI | 10 | 12 | 14 | 15 | 15 | 14 | 14 | 13 | 14 | 12 | 10 | 8 |
| Mexico City UVI | 10 | 12 | 14 | 15 | 15 | 14 | 14 | 13 | 14 | 12 | 10 | 8 |
| Puebla UVI | 10 | 12 | 14 | 15 | 15 | 15 | 15 | 14 | 14 | 13 | 10 | 9 |