Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors of Swellendam, South Africa, a picturesque town nestled in a BSk climate zone. As the sun rises, so do the levels of ultraviolet radiation that can lead to sunburn and long-term skin health issues. With midday UV Index readings peaking at 4, it's vital to be aware of the risks associated with sun exposure, especially during the warmer months. By learning about UV levels, you can take proactive steps to protect your skin and enjoy the beautiful South African outdoors safely.
The UV Index throughout the day reveals a dynamic pattern of sun intensity. In the morning, it starts off low, peaking at 1 by 09:00. As the sun climbs higher, we see a steady increase with the index reaching 3 by 11:00. The highest point occurs from 12:00 to 13:00, where the UV Index hits a robust 4, indicating a need for sun protection during those hours. Following this peak, the index gradually declines, returning to 2 at 15:00, and then dropping back down to 0 by 18:00, marking the end of significant UV exposure for the day. Plan your outdoor activities accordingly to stay safe under the sun!
| 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 | 3 | moderate | 30 min |
| 15:00 | 2 | low | 45 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 experiences significant seasonal fluctuations, peaking during the winter months. January and February record an extreme UV Index of 14 and 13 respectively, with a rapid burn time of just 10 minutes. This trend continues into March with an index of 11. As spring arrives in April, the UV Index drops to 8 (very high), allowing for 15 minutes of exposure before burning occurs. From May to July, the UV Index levels decrease to 5 and 4 (moderate), extending burn times to 30 minutes. However, the UV exposure rises again in late summer, with August at 6 (high) and 25 minutes of burn time. As fall approaches, the UV levels rebound in September to 9 (very high) before shifting back to extreme levels in October (11) and November (12), both with a burn time of 10 minutes. December mirrors January, reaching UV levels of 14. Visitors and residents should take precautionary measures during high-risk months (January to March, October to November) by applying sunscreen, wearing protective clothing, and limiting sun exposure during peak hours to mitigate the risks associated with high UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cape Town UVI | 14 | 13 | 11 | 8 | 5 | 3 | 4 | 6 | 9 | 11 | 12 | 14 |
| Swellendam | 14 | 13 | 11 | 8 | 5 | 4 | 4 | 6 | 9 | 11 | 12 | 14 |
| Durban UVI | 14 | 13 | 12 | 9 | 6 | 4 | 5 | 7 | 9 | 11 | 13 | 15 |
| Johannesburg UVI | 15 | 15 | 13 | 10 | 7 | 6 | 6 | 8 | 11 | 12 | 14 | 16 |
| Pretoria UVI | 16 | 15 | 13 | 10 | 7 | 6 | 6 | 9 | 11 | 13 | 14 | 16 |
| Soweto UVI | 16 | 15 | 13 | 11 | 7 | 6 | 6 | 8 | 11 | 13 | 15 | 16 |