Last updated: June 2, 2025
In Koster, South Africa, being aware of the UV Index is crucial for maintaining healthy skin while enjoying the outdoors. Understanding UV levels helps in preventing sunburn and long-term skin damage, particularly as the sun's intensity peaks during the midday hours. With a Cwa climate, Koster experiences varied UV exposure risks throughout the year, especially from late morning to early afternoon when the UV Index can reach as high as 6. By tracking the UV Index, residents and visitors can take proactive measures to protect themselves, ensuring a safe and enjoyable time under the sun.
The UV Index today showcased a notable increase from the early morning hours, starting at a gentle 1 at 07:00 and 08:00. As the sun rose higher in the sky, the index climbed steadily, reaching a significant 6 by 12:00, indicating a peak in UV radiation and the need for sun protection. The afternoon saw a slight decline, with values dropping to 4 at 14:00 and falling further to 2 by 15:00. As the day wound down, the UV index returned to a safer range, ending the day at 0 by 19:00. It’s crucial to stay informed and safeguard your skin during those high UV hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 5 | moderate | 30 min |
| 12:00 | 6 | high | 25 min |
| 13:00 | 5 | moderate | 30 min |
| 14:00 | 4 | 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 |
Throughout the year, the UV Index indicates significant seasonal variations, with the highest values occurring from January to April, where it reaches an extreme level of 16 in January and December, with a burn time of just 10 minutes. February and March also maintain an extreme exposure category (UV Index 15 and 13 respectively), necessitating cautious sun protection measures. April sees a slight decrease to a UV Index of 11, still categorized as extreme. As the warmer months approach, the UV Index relaxes to 7 in May and 6 in June and July, classified as high, allowing for longer burn times of 25 minutes. However, August brings a spike back to a very high UV Index of 9, with a shorter burn time of 15 minutes. From September to November, we again encounter extreme UV levels, with indices hovering around 11 to 14 and consistent burn risks of 10 minutes. Visitors and residents are advised to exercise heightened sun safety measures, particularly during the high-risk months of January through April, and again in September through November, to prevent sunburn and skin damage. Regular application of broad-spectrum sunscreen, protective clothing, and seeking shade during peak sun hours are essential practices.
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 |
| 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 |
| Koster | 16 | 15 | 13 | 11 | 7 | 6 | 6 | 9 | 11 | 13 | 14 | 16 |