Last updated: July 2, 2025
Understanding the UV Index is essential for residents and visitors in Florence, United States, as it plays a pivotal role in safeguarding skin health and preventing sunburns. With the region's humid subtropical climate, exposure to harmful ultraviolet rays can peak dramatically, especially during the summer months. On brighter days, the UV Index can soar to a level of 12 around midday, indicating an increased risk of harm to unprotected skin. Staying informed about daily UV levels not only helps you enjoy the outdoors safely but also promotes long-term skin health, enabling you to fully embrace all that Florence has to offer under the sun.
As the sun rises, the UV Index starts at a mild 1 at 7:00 AM and remains low until 9:00 AM, where it climbs to 3. By 10:00 AM, the index accelerates to a moderate 5, but it’s at 11:00 AM that the heat intensifies, reaching 8. The peak occurs at 12:00 PM with a staggering value of 10, followed by the highest point of the day at 1:00 PM and 2:00 PM, where it maxes out at 12. After this peak, the index gradually declines: it drops to 10 by 3:00 PM and continues to decrease to 7 at 4:00 PM. By the late afternoon, the intensity wanes, falling to 5 at 5:00 PM and back down to 2 by 6:00 PM, before settling at 1 again as day turns to dusk by 7:00 PM. Remember to shield yourself during the midday hours when the UV radiation is at its most intense!
| 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 | 12 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The UV Index varies significantly throughout the year, with the highest levels occurring from March to September. During this period, particularly in April, May, June, and July, the UV Index reaches extreme levels of 11 and 12, resulting in a burn time of just 10 minutes for unprotected skin. February marks the beginning of high-risk months, with an index of 7 and burn time of 25 minutes. As autumn approaches, the UV Index decreases, but even in October, the index remains high at 8. Residents and visitors are advised to take extra precautions during these months, such as applying sunscreen, wearing protective clothing, and seeking shade to minimize sun exposure, especially during peak hours. In contrast, January, November, and December see lower UV levels (ranging from 4 to 6), where exposure is still moderate but poses less risk.
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 |
| Florence | 5 | 7 | 9 | 11 | 11 | 12 | 12 | 11 | 11 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |