Last updated: July 2, 2025
In Cesky Krumlov, understanding the UV Index is essential for safeguarding your skin and overall health. With peak levels reaching 9 during the midday hours, awareness of UV exposure is crucial to prevent sunburn and long-term skin damage. The city's Cfb climate offers a blend of sunny days and overcast skies, but even on less sunny days, UV rays can cause harm. By keeping an eye on the UV Index, locals and visitors alike can enjoy the beautiful surroundings while taking crucial steps to protect themselves from harmful sun exposure.
As the sun rises, the UV Index begins its gradual ascent. At 7:00 AM, it starts at a modest 1, indicating minimal risk. By 8:00 AM, it rises to 2, still manageable for early risers. The intensity picks up at 9:00 AM with a 3, signaling the need for a little sunscreen. The peak arrives between 11:00 AM and 1:00 PM, where it soars to a striking 9 at 1:00 PM, which suggests strong sun protection is essential. Following this, the index slips down, recorded at 8 at 2:00 PM and 7 at 3:00 PM, offering a brief reprieve. As the afternoon fades into evening, the UV Index drops steadily, landing back at 1 by 7:00 PM. Stay informed and protect your skin during those peak 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 | 7 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 7 | 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, the UV Index demonstrates notable seasonal variations that affect exposure risk. January and February have relatively low to moderate UV levels (Index 2-3), with safe burn times of 45 and 30 minutes respectively. As spring approaches, March sees a rise to an index of 5, and by April, it reaches 6, marking the beginning of high-risk months. The most critical period arrives in May and June, where the UV Index peaks at 8-9, indicating very high exposure risk and a reduced burn time of just 15 minutes. July and August maintain this peak, before tapering off in September with a return to a high risk (UV Index 6). October brings a moderate reduction (Index 4), while winter months November and December drop back to low levels. Visitors and residents should be particularly vigilant during May through September, using sunscreen and protective clothing to minimize harmful effects during these high-risk months.
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 |
| 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 |
| Cesky Krumlov | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 6 | 4 | 2 | 1 |