Last updated: June 2, 2025
In Zanzibar, Tanzania, understanding the UV Index is crucial for both locals and visitors alike, as it profoundly impacts sun safety and skin health. With the island's tropical climate, the risk of harmful UV exposure can soar, particularly during midday when the UV Index reaches its peak at levels of 10. This awareness is essential not only for preventing painful sunburns but also for safeguarding against long-term skin damage. As you enjoy the stunning beaches and vibrant culture of Zanzibar, staying informed about UV levels will help you protect your skin and enhance your overall wellness.
The UV Index throughout the day showcases a dynamic curve, peaking impressively between 12:00 PM and 1:00 PM with a remarkable score of 10, indicating a high risk of harm from unprotected sun exposure. As the sun rises, the index starts low at 1 by 07:00 AM, gradually increasing to 2 by 08:00 AM, before climbing more steeply to reach 6 by 10:00 AM. The intensity continues to rise until its zenith, with values of 9 at 11:00 AM and the maximum of 10 at noon. After this peak, the UV Index begins its descent, dropping to 8 by 2:00 PM, then gradually tapering off to 5 by 3:00 PM and further to 1 by late afternoon, ultimately falling to 0 by 7:00 PM. It's a reminder to stay protected during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 5 | moderate | 30 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 shows a consistent pattern of extremely high levels throughout the first eight months of the year, with a notable peak from January to April, where it maintains a value of 14 and an extreme exposure category, indicating a burn time of just 10 minutes. Even in May, the UV Index remains high at 12. As we enter the summer months, June and July present a slight decrease to 10, categorized as very high, allowing for a marginally longer burn time of 15 minutes. However, August sees a return to extreme levels at 12, continuing through September, October, and November with 13. Thus, the highest-risk months for UV exposure are from January to April, as well as August to November. Visitors and residents are advised to take precautionary measures during these months, including the use of sunscreen, protective clothing, and seeking shade during peak sunlight hours to minimize the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Zanzibar | 14 | 14 | 14 | 14 | 12 | 10 | 10 | 12 | 13 | 13 | 13 | 13 |
| Dar es Salaam UVI | 14 | 14 | 15 | 14 | 12 | 10 | 10 | 12 | 13 | 13 | 13 | 13 |
| Mwanza UVI | 14 | 15 | 16 | 15 | 13 | 11 | 11 | 13 | 14 | 13 | 13 | 13 |
| Arusha UVI | 15 | 16 | 16 | 16 | 14 | 12 | 12 | 13 | 14 | 14 | 13 | 14 |
| Mbeya UVI | 16 | 16 | 16 | 16 | 13 | 11 | 11 | 13 | 14 | 14 | 14 | 15 |