Last updated: July 2, 2025
In San Antonio, Chile, being aware of the UV Index is crucial for protecting your skin and overall health. Understanding the varying levels of UV exposure throughout the day helps prevent sunburn and long-term skin damage. With a Mediterranean climate (Csb), San Antonio experiences significant UV radiation, particularly from late morning to early afternoon, when the index can reach levels of 4. This highlights the need for sun safety practices, especially during peak hours. Stay informed and safeguard your skin while enjoying the beautiful sunny days that San Antonio has to offer!
The UV Index throughout the day shows a gentle morning rise, starting at 0 at 07:00, then climbing to 1 by 08:00 and staying steady until it reaches 2 at 10:00. Midday brings the peak intensity, with the index soaring to 4 from 12:00 to 14:00, indicating a significant need for sun protection. As the afternoon wears on, the UV levels gradually decline, tapering back down to 1 by 16:00, before dropping to 0 after 18:00. This daily pattern highlights the importance of being mindful of UV exposure, especially between noon and early afternoon when the sun’s rays are at their strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 0 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 1 | low | 45 min |
| 10:00 | 2 | low | 45 min |
| 11:00 | 3 | moderate | 30 min |
| 12:00 | 4 | moderate | 30 min |
| 13:00 | 4 | moderate | 30 min |
| 14:00 | 4 | moderate | 30 min |
| 15:00 | 3 | moderate | 30 min |
| 16:00 | 1 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 0 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV index exhibits significant seasonal variation, with extreme levels persisting from January to March and returning in October to November, highlighting these months as high-risk periods for skin damage, with a rapid burn time of just 10 minutes. The spring month of April marks a transition to a very high category with a slightly increased burn time of 15 minutes before tapering to moderate levels in May through July, where individuals can safely enjoy up to 30 minutes of sun exposure. However, by August, UV levels rise to high, necessitating 25 minutes of careful exposure. In September, the risk escalates again to very high before returning to extreme levels by late autumn. Residents and visitors should take precautions during high-risk months by applying sunscreen, wearing protective clothing, and seeking shade during peak sun hours to minimize UV-related health risks.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Santiago UVI | 14 | 12 | 11 | 7 | 5 | 3 | 4 | 6 | 8 | 11 | 12 | 14 |
| Valparaiso UVI | 14 | 12 | 11 | 8 | 5 | 4 | 4 | 6 | 8 | 11 | 12 | 14 |
| Vina del Mar UVI | 14 | 12 | 11 | 8 | 5 | 4 | 4 | 6 | 8 | 11 | 12 | 14 |
| San Antonio | 14 | 13 | 11 | 8 | 5 | 3 | 4 | 6 | 8 | 11 | 13 | 14 |
| Puente Alto UVI | 15 | 14 | 12 | 8 | 6 | 4 | 6 | 8 | 11 | 12 | 14 | 15 |
| Antofagasta UVI | 15 | 15 | 13 | 10 | 8 | 6 | 7 | 9 | 11 | 14 | 15 | 15 |