Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Randfontein, South Africa, where the high-altitude climate can lead to significantly increased UV exposure. As the sun's rays can lead to skin damage, regular monitoring of UV levels is essential for effective sunburn prevention and maintaining long-term skin health. With typical midday values rising to a risk level of 6, it's important to remain vigilant to protect yourself from harmful effects. In Randfontein's Cwb climate zone, be aware that UV exposure can vary significantly throughout the day, particularly peaking between 10:00 AM and 1:00 PM, making awareness and proactive measures vital for safe outdoor activities.
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, UV radiation exposure exhibits significant seasonal variations, with the highest risk months peaking in January, February, and March, where the UV Index reaches an extreme level of 16 to 13, allowing for a dangerously short burn time of just 10 minutes. The trend continues into April and September, which also maintain an extreme UV Index of 11. As summer approaches, a slight decrease in UV Index is observed in May to July, with values ranging from 6 to 7, indicating a high exposure risk but allowing for longer burn times of 25 minutes. However, high caution is advised during August when the UV Index spikes back to 8 (very high). As the year closes, November and December mirror the extreme levels seen at the start of the year, necessitating constant vigilance. Therefore, visitors and residents should adopt protective measures, such as wearing sunscreen and protective clothing, especially during peak UV times, and seek shade whenever possible, particularly in the high-risk months of January through March and September through November.
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 |
| Randfontein | 16 | 15 | 13 | 11 | 7 | 6 | 6 | 8 | 11 | 13 | 15 | 16 |
| Soweto UVI | 16 | 15 | 13 | 11 | 7 | 6 | 6 | 8 | 11 | 13 | 15 | 16 |