Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in San Francisco, Colombia, where the unique Cfb climate results in varying levels of sun exposure throughout the day. With UV levels peaking between 11:00 AM and 1:00 PM, reaching as high as 16, awareness of these levels is vital for sunburn prevention and overall skin health. By keeping an eye on the UV Index, you can make informed decisions about when to seek shade, wear protective clothing, or apply sunscreen, helping to reduce the risk of harmful skin effects and enjoy the beautiful, sunlit environment safely.
At 07:00, the UV Index starts gently at 1, but by 08:00, it begins to rise, reaching 3. As the sun ascends, an increase in intensity is evident, soaring to 7 by 09:00. The peak of the day occurs between 11:00 and 12:00, where the UV Index hits its highest point at 16, emphasizing the need for sun protection during these hours. As the afternoon rolls in, the index gradually declines, dropping to 15 at 13:00 and further decreasing to 12 by 14:00. The latter part of the day sees a significant drop, with readings falling back to 7 at 15:00 and tapering off to 1 by 17:00. The UV levels finally relax to 0 by 19:00, marking the end of a sun-drenched day. Always stay vigilant and protect your skin during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 11 | extreme | 10 min |
| 11:00 | 15 | extreme | 10 min |
| 12:00 | 16 | extreme | 10 min |
| 13:00 | 15 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV Index data indicates extreme levels of ultraviolet radiation throughout the year, with particularly high values in March (19) and April (19). Residents and visitors should be especially cautious during these months, as they coincide with the highest risk for skin damage and sunburn, requiring only 10 minutes of sun exposure to receive harmful effects. January through May also reflect high risk with UV Index values consistently above 17, while October through December demonstrate slightly reduced values, yet still pose a risk. It’s advisable to use sunscreen, wear protective clothing, and limit sun exposure during peak hours from January through May and again in the fall, ensuring skin health is prioritized year-round.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Barranquilla UVI | 11 | 12 | 14 | 14 | 13 | 12 | 13 | 13 | 13 | 13 | 11 | 10 |
| Cartagena UVI | 11 | 11 | 13 | 15 | 13 | 13 | 12 | 13 | 13 | 13 | 11 | 10 |
| Medellin UVI | 14 | 15 | 17 | 16 | 16 | 14 | 14 | 15 | 14 | 14 | 13 | 12 |
| Cali UVI | 15 | 16 | 17 | 17 | 15 | 14 | 14 | 14 | 15 | 14 | 13 | 12 |
| Bogota UVI | 15 | 16 | 18 | 18 | 17 | 15 | 15 | 16 | 15 | 15 | 14 | 13 |
| San Francisco | 17 | 17 | 19 | 19 | 17 | 14 | 15 | 15 | 16 | 17 | 15 | 13 |