Last updated: July 2, 2025
Being aware of the UV Index is crucial for residents and visitors in Janov nad Nisou, as it plays a significant role in protecting skin health and preventing sunburn. Understanding the daily UV levels helps you plan your outdoor activities and safeguard against harmful effects, especially during the peak hours when indices can soar to 8 around midday. Nestled in a Cfb climate zone, Janov nad Nisou experiences a varied climate, but even in cooler months, UV radiation can pose risks. Awareness of these levels is your first line of defense in enjoying the beautiful outdoors while keeping your skin safe and healthy.
As the sun rises, the UV Index begins its ascent, starting at a mere 1 at 7:00 AM. By 8:00 AM, it climbs to 2, but it’s by 9:00 AM that we see a moderate rise to 3. The intensity peaks between 11:00 AM and 1:00 PM, hitting a high of 8, indicating that sun protection methods should be in full swing. As the afternoon progresses, values slightly decrease, with the UV Index dropping to 6 by 3:00 PM and then gradually retreating to 1 by 7:00 PM. This hourly data serves as a reminder to stay vigilant about sun safety during the mid-day hours when UV exposure is at its highest.
| 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 | 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 | 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 levels experience significant fluctuations, with high-risk months identified as April through August, during which the UV Index can reach as high as 8 and fall within the very high exposure category. Specifically, June and July are the peak months for UV exposure, requiring extra caution as the burn time shortens to just 15 minutes. In contrast, January, November, and December present the lowest UV indices, categorized as low exposure, allowing for safer outdoor activities with extended burn times of 45 minutes. To ensure safety, visitors and residents should remain vigilant in high-risk months, applying sunscreen, wearing protective clothing, and seeking shade during peak hours, while enjoying the more forgiving UV levels during the winter months.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Janov nad Nisou | 2 | 3 | 4 | 6 | 7 | 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 |