Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors of Sanibel, Florida, where the sun shines bright and high. Being aware of UV levels not only helps in preventing sunburn but also plays a significant role in maintaining long-term skin health. Sanibel's tropical climate brings consistently high UV exposure, with peak levels often reaching 12 during midday hours. With this in mind, it's essential to not only enjoy the beautiful beaches but also to take protective measures against harmful UV rays. Stay informed and safeguard your skin while soaking up the sun on this stunning island!
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 |
During the year, UV Index levels experience significant fluctuations, with the highest risk months occurring from April to September, where the index peaks at 12, categorized as extreme. This period indicates a burn time of just 10 minutes, making sun protection critically important. February and March also present high risks, with indices of 9 and 10, respectively. Visitors and residents are advised to take precautions, such as wearing sunscreen, protective clothing, and sunglasses, especially during the peak hours of sunlight. As UV levels drop in the fall and winter months, from October to December, while still significant, the levels decrease to a maximum of 8 in November, allowing for somewhat safer outdoor activities. Always remain vigilant about UV exposure, regardless of the season.
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 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |
| Sanibel | 6 | 9 | 10 | 12 | 12 | 12 | 12 | 12 | 11 | 10 | 8 | 6 |