Last updated: July 2, 2025
Being aware of the UV Index is crucial for residents and visitors in Vienna, United States, as it helps protect against the harmful effects of ultraviolet radiation. Understanding UV levels is essential for preventing sunburn, maintaining skin health, and minimizing the long-term risks of skin cancer. With a climate characterized by warm summers and ample sunshine, Vienna experiences varying UV exposure throughout the day, peaking at levels that can reach 11 from late morning to early afternoon. Stay informed about the UV Index to enjoy the sun safely and protect your skin from potential damage!
The UV Index throughout the day exhibits a remarkable peak, beginning at a low 1 in the early hours, gradually rising to 5 by 10:00. As the sun reaches its zenith, the index soars to an impressive 10 at 12:00, hitting a maximum of 11 from 13:00 to 14:00. This intense exposure makes midday the most critical time for sun protection. As the afternoon progresses, the index begins to dip, falling to 7 at 16:00, and winding down to a gentle 3 by 18:00. By 19:00, the UV Index drops back to 1, signaling a return to safer sun conditions. Planning outdoor activities? Make sure to take precautions from late morning to mid-afternoon, when the sun’s rays are most powerful!
| 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 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
The UV Index exhibits significant seasonal variation, peaking during the summer months. From January (UV Index 4) to February (UV Index 7), exposure remains moderate to high, with burn times shortening as spring approaches. The months of March and April see a sharp increase in UV levels (9 and 10 respectively), indicating very high risk for sunburn, with a burn time of just 15 minutes. The extreme category dominates from May to August (UV Index 11), where even brief sun exposure can result in burns within 10 minutes. As we move into September and October, the index drops to 10 and 8, maintaining a very high risk, before returning to a moderate level in November and December (UV Index 6 and 4). Visitors and residents are strongly advised to take precautions, especially from March through October, by wearing protective clothing, using sunscreen, and seeking shade during peak sun hours to minimize the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Vienna | 4 | 7 | 9 | 10 | 11 | 11 | 11 | 11 | 10 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |