Last updated: June 2, 2025
Understanding the UV Index is essential for the residents of Louisa, United States—a region that experiences varying UV exposure throughout the year. Being aware of these levels is crucial for preventing sunburn and protecting skin health, especially during the peak hours when the UV index soars to 10 around noon and early afternoon. With Louisa's Cfa climate, characterized by hot summers, residents face increased risks of UV-related skin damage. Staying informed about UV levels can help you enjoy the sun safely, ensuring your outdoor activities remain both enjoyable and healthy.
The UV Index reveals a dynamic ascent and descent throughout the day, peaking with intensity during midday. Starting at a gentle 1 at 7:00 AM, it climbs steadily, reaching 10 by 1:00 PM and maintaining this highest level until 2:00 PM. This critical window indicates significant sun exposure, and it’s essential to take precautions. As the afternoon progresses, the index begins to taper off, dropping to 8 at 3:00 PM, then gradually falling to 1 by 7:00 PM. This data highlights the importance of being sun-smart during the peak hours to minimize UV exposure risks.
| 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 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, ultraviolet (UV) radiation levels fluctuate significantly, influencing exposure risks for both residents and visitors. January to February begins with a moderate UV Index of 3, increasing to 6 in February, indicating higher caution is needed as the potential for skin damage grows. By March, the Index reaches 7, and from April through September, it peaks at a very high level of 9 to 10, particularly in the summer months of May, June, July, and August. These months represent the highest-risk periods for UV exposure, with a critical burn time of just 15 minutes. As the year progresses, October sees a decrease to a high level of 7, followed by a return to moderate levels in November (5) and December (3). It is crucial for everyone to take precautions during high-risk months, such as wearing sunscreen, protective clothing, and seeking shade to mitigate the risk of UV-related health issues.
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 |
| Louisa | 3 | 6 | 7 | 9 | 10 | 10 | 10 | 10 | 8 | 7 | 5 | 3 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |