Last updated: July 2, 2025
In Rez, Czech Republic, being mindful of the UV Index is crucial for maintaining skin health and preventing sunburn. As the sun’s intensity fluctuates throughout the day, knowing the UV levels can help you protect yourself from harmful rays. With a Cfb climate characterized by mild summers, UV exposure can still reach significant levels—peaking at 8 around midday. Stay informed and take the necessary precautions to enjoy the beautiful days safely!
The UV Index throughout the day presents a dynamic landscape of sun exposure. Starting off at a mild 1 at 7:00 AM, the intensity gradually rises, hitting 2 by 8:00 AM and 3 by 9:00 AM. The real peak emerges at 12:00 PM and 1:00 PM, where it reaches a robust 8—a signal to seek shade and cover up! As the afternoon progresses, the index gently declines to 6 by 3:00 PM, before tapering off further to 2 by 6:00 PM, and finally returning to a cool 1 by 7:00 PM. This data reminds us to be sun-smart during those critical midday hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 5 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest risk occurring during the summer months of May to August. During this period, the UV Index peaks at 8, categorized as very high, with a burn time of just 15 minutes. In contrast, the lower risk months of January, February, November, and December have UV Index values of 2 or lower, indicating low exposure levels and longer burn times of 45 minutes. March and April also present moderate risk (UV Index 4-5), where individuals should limit sun exposure to 30 minutes. It is essential for both visitors and residents to take precautions during high-risk months by seeking shade, wearing protective clothing, and applying sunscreen to minimize the risk of sunburn and long-term skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rez | 2 | 2 | 4 | 5 | 8 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |
| Prague UVI | 2 | 3 | 4 | 5 | 7 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |
| Ostrava UVI | 2 | 2 | 4 | 6 | 7 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |
| Olomouc UVI | 2 | 3 | 4 | 6 | 7 | 8 | 8 | 7 | 6 | 4 | 2 | 2 |
| Pilsen UVI | 2 | 3 | 5 | 6 | 8 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |
| Brno UVI | 2 | 3 | 5 | 6 | 8 | 8 | 8 | 7 | 6 | 4 | 2 | 2 |