Last updated: May 3, 2025
Understanding the UV Index in Merrimack, United States, is crucial for safeguarding your skin against harmful ultraviolet radiation. With peak UV levels reaching as high as 9 during midday, awareness of these fluctuations can significantly aid in sunburn prevention and promote long-term skin health. Located in a Dfb climate zone, Merrimack experiences a mix of seasonal changes, which can lead to varying UV exposure risks throughout the year. By staying informed about the daily UV Index, you can enjoy the outdoors while keeping your skin protected and healthy.
As the sun rises, the UV Index gradually climbs, starting at a mild 1 at 07:00. By 08:00, it nudges up to 2, signaling a gentle start to the day. The real intensity kicks in at 09:00, reaching 4, and peaks impressively at 12:00 with a high of 9. The UV levels remain strong throughout the afternoon, holding at 9 until 13:00, before tapering off slightly to 8 at 14:00. By 15:00, it decreases to 7, and as the sun begins its descent, the index drops dramatically, hitting 4 by 16:00 and further declining to a safe 1 by 18:00 and 19:00. Staying sun-safe during the peak hours between 10:00 and 14:00 is essential to protect your skin from harmful UV rays!
| 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 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The seasonal UV Index shows significant variation, with high-risk months occurring from April through August when the UV Index reaches levels classified as very high. During these months, exposure times drop to just 15 minutes, emphasizing the need for protective measures. In April, the UV Index escalates to 8, peaking at 10 in June before slightly declining to 9 in July and August. As fall approaches, the risk decreases; however, September and October still pose a high risk with UV Index values of 7 and 6, respectively. For visitors and residents, it is crucial to take precautions, such as wearing sunscreen, hats, and protective clothing, especially during peak hours in these high-risk months. January through March and November through December present lower risks, with UV levels generally moderate to low; these months require less stringent sun protection but still warrant caution.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Merrimack | 3 | 5 | 5 | 8 | 9 | 10 | 9 | 9 | 7 | 6 | 3 | 2 |
| 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 |