Last updated: July 2, 2025
Understanding the UV Index in Jefferson, United States is crucial for protecting your skin and overall health. As UV levels fluctuate throughout the day, being aware of these changes can help you prevent sunburn and long-term skin damage. With Jefferson's humid subtropical climate, sun exposure can be particularly intense during peak hours—especially between 10 AM and 2 PM when the UV Index reaches its highest point at 11. Stay informed and take proactive steps to enjoy the sun safely!
As the sun rises, the UV Index begins its modest ascent, starting at a gentle 1 around 7:00 AM and 8:00 AM. By 9:00 AM, it picks up to 3, hinting at a sunnier day ahead. The peak intensity occurs from 11:00 AM to 1:00 PM, where it skyrockets to a striking 10 at 12:00 PM, reaching an impressive 11 by 1:00 PM—perfect for those sun-seeking adventurers! However, after this zenith, the UV Index gradually declines, dropping to 9 by 3:00 PM and further easing to a 4 by 5:00 PM. By 6:00 PM, it falls to 2, and as the sun sets, it returns to a safe 1 by 7:00 PM. Remember to take precautions during those peak hours to protect your skin from harmful rays!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 8 | 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 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV index values fluctuate significantly, with peaks during the summer months. From January to March, the UV index rises from a moderate level of 4 to a very high 8, indicating an increasing risk for skin damage. The high-risk months are clearly identified as May through July, with an extreme index of 11, where the burn time shortens to just 10 minutes. This intensity decreases slightly in August and September but remains very high at 10 and 9, respectively. As the year closes, UV levels drop back to moderate levels by December. Visitors and residents should take precautions during the high-risk months by using sunscreen, wearing protective clothing, and seeking shade to minimize the risk of sunburn and long-term 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 |
| Jefferson | 4 | 6 | 8 | 10 | 11 | 11 | 11 | 10 | 9 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |