Last updated: July 2, 2025
Understanding the UV Index is essential for residents and visitors in Lesna, Czech Republic, where sun exposure risks can vary significantly throughout the day. As the climate here falls under the Dfb category, sunny days can lead to higher UV levels, particularly around midday when the Index peaks. By being aware of local UV levels, you can effectively prevent sunburn, protect your skin health, and enjoy the outdoors safely. With the UV Index reaching its maximum of 8 between noon and 2 PM, it's crucial to take precautions to shield yourself from harmful rays and maintain your overall well-being.
The UV Index throughout the day reveals a clear trajectory of increasing intensity, peaking at 12:00 PM when it reaches an impressive 8. Starting from a gentle 1 at 7:00 AM, it gradually climbs, hitting 5 by 10:00 AM. The sun’s strength becomes undeniable as it soars to 7 at 11:00 AM and maintains a robust 8 from 12:00 PM to 2:00 PM. As the afternoon progresses, the index drops to 6 by 3:00 PM and continues to decrease, settling back to a mild 1 by 7:00 PM. This hourly data highlights the importance of sun protection during the peak hours when the UV Index is at its highest, particularly from 11:00 AM to 2:00 PM.
| 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 | 5 | moderate | 30 min |
| 11:00 | 7 | 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 | 4 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The UV Index experiences notable fluctuations throughout the year, influencing both sun exposure and risk levels for skin damage. During the winter months, from December to February, the UV Index remains low (1-2), allowing for longer burn times of 45 minutes, making this a relatively safer period for sun exposure. However, as spring approaches, particularly in March, the UV levels rise to a moderate index of 4, indicating the need for increased caution with a reduced burn time of 30 minutes. The high-risk months occur from late spring to mid-summer, with May reaching an index of 7 and June and July peaking at 8, categorized as very high, significantly shortening safe exposure to just 15 minutes. As summer transitions to fall, the risk reduces but remains considerable in August (UV Index 7) and September (UV Index 6), before tapering off in the fall months of October through December. Visitors and residents are advised to protect their skin during high UV periods by wearing sunscreen, hats, and protective clothing, particularly in the peak months from April to August.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 |
| Lesna | 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 |