Last updated: June 2, 2025
In Charleston, United States, understanding the UV Index is crucial for protecting your skin and overall health. With peak UV levels often reaching as high as 11 during the midday hours, residents and visitors alike must be vigilant about sun exposure to prevent painful sunburns and long-term skin damage. Charleston's Cfa climate brings warm, sunny days, resulting in elevated UV radiation risks, especially in summer. By staying informed about daily UV levels, you can take proactive measures to enjoy the beautiful South Carolina weather while keeping your skin safe.
The UV Index throughout the day reveals a dramatic rise in solar intensity. Starting at a mild 1 at 07:00, it climbs steadily, reaching 2 by 08:00. The real spike occurs as the sun climbs higher, with the index jumping to 4 at 09:00, before peaking at a striking 11 by 13:00—the highest risk of the day. After this peak, the UV levels gradually taper off, dropping to 8 at 15:00, and settling to a gentle 2 by 18:00. Remember to don that sunscreen during the midday hours to protect your skin from the sun’s powerful rays!
| 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 | 7 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 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, seasonal changes in UV Index levels highlight varying risks associated with sun exposure. From January to February, UV levels remain moderate, with burn times of 30 minutes, making it a relatively safer period for outdoor activities. However, as March approaches, the UV Index escalates to 6, indicating higher caution is needed. The spring and summer months show a significant increase, peaking in June with an extreme UV Index of 11, where burn time reduces to just 10 minutes. High-risk months include April through August, with very high to extreme levels; visitors and residents should take extra precautions, like wearing sunscreen, hats, and protective clothing during these months. As the year progresses into October and November, UV levels decrease, returning to moderate levels by December, providing a safer environment for outdoor enjoyment. It’s essential for everyone to stay informed about UV levels and adjust their sun safety practices accordingly.
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 |
| Charleston | 3 | 5 | 6 | 9 | 10 | 11 | 10 | 9 | 8 | 6 | 4 | 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 |