Last updated: August 1, 2025
Understanding the UV Index is crucial for residents of Hopkinton, United States, as it directly impacts your skin health and sunburn prevention strategies. With the region's Dfa climate, Hopkinton experiences periods of high UV exposure, especially during the midday hours when the UV Index can reach a peak of 10. By being aware of daily UV levels, you can take proactive measures to protect yourself and your loved ones, ensuring safer outdoor experiences while minimizing long-term skin damage. Don’t let the sun catch you off guard—stay informed, stay safe!
From 07:00 to 08:00, the UV Index starts off mild with a maximum of 1 to 2, making it a safe time for early outdoor activities. As the sun climbs higher, the UV levels rise sharply, reaching 4 by 09:00 and hitting 6 by 10:00. The intensity peaks at 13:00 with a significant 10, indicating high exposure risk, perfect for applying sunscreen and seeking shade. As we move into the afternoon, levels gradually decrease, tapering to 9 by 14:00 and falling back to a more manageable 4 by 17:00. By evening, UV levels drop to 2 at 18:00 and retreat to 1 by 19:00, marking a safe return for those looking to enjoy twilight outdoors. Remember, it's essential to stay vigilant during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | high | 25 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, the UV Index experiences significant seasonal changes, with the highest risk occurring during the late spring and summer months. From April to September, the UV Index reaches very high to extreme levels, particularly peaking in June at an Index of 11, where the burn time drops to just 10 minutes. Consequently, visitors and residents should be particularly vigilant during this period, especially in May through August, where the burn time remains critical at 15 minutes for high UV levels. In contrast, the months from October to March exhibit a moderate UV Index, with safer burn times of 30 minutes. It is advisable for everyone to adopt appropriate sun protection measures, such as wearing sunscreen, protective clothing, and seeking shade, during those peak months to minimize skin damage and health risks.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hopkinton | 3 | 4 | 5 | 8 | 9 | 11 | 10 | 9 | 8 | 5 | 3 | 3 |
| 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 |