Last updated: July 2, 2025
In San Juan, United States, being aware of the UV Index is crucial for maintaining healthy skin and preventing sunburn, especially given the region's temperate climate. With UV levels reaching their peak at 12 during midday, understanding these fluctuations helps residents and visitors make informed choices about sun protection. As you enjoy the beautiful outdoor activities San Juan has to offer, staying mindful of UV exposure not only safeguards your skin health but also enhances your overall well-being. So, whether you're lounging on the beach or hiking in the nearby hills, keep an eye on the UV Index to enjoy the sun safely!
Throughout the day, the UV Index experiences a dynamic shift, peaking at an impressive 13 between 1 PM and 2 PM, indicating a high risk of harm from unprotected sun exposure. The morning starts gently, with a UV Index of 1 at 7 AM, gradually rising to 4 by 9 AM. As the sun inches higher, the intensity increases sharply, reaching 10 by 11 AM and soaring to 12 by noon. Post-peak, the index begins to decline, dropping to 10 at 3 PM, before settling back to a mild 2 by 6 PM. This clear progression emphasizes the importance of sun protection during the midday hours when the UV Index is at its highest. Enjoy the sunshine, but remember to stay safe! ☀️
| 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 | 10 | very high | 15 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 10 | 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 levels exhibit significant seasonal changes, with high-risk months primarily falling between February and September. The index peaks in June and July at 13, categorized as extreme, indicating that unprotected skin can burn in as little as 10 minutes. March, April, and May also see very high to extreme levels, with UV indices of 10 to 12. Conversely, January, November, and December present lower risks with moderate to high levels, allowing for longer exposure times. Residents and visitors should take precautions during high-risk months by wearing sunscreen, protective clothing, and seeking shade, especially during peak sun hours to minimize the risk of 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 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |
| San Juan | 5 | 8 | 10 | 11 | 12 | 13 | 13 | 12 | 11 | 8 | 6 | 4 |