Last updated: June 2, 2025
In St Johnsbury, Vermont, being aware of the UV Index is essential for maintaining skin health and preventing sunburn. Understanding the daily UV levels informs residents and visitors when to seek shade or apply sunscreen, ultimately helping to reduce the risk of long-term skin damage. With its Dfb climate, St Johnsbury experiences varying UV exposure throughout the year, with peak levels reaching a notable 10 during midday in the summer months. By staying informed about the UV Index, you can enjoy the beautiful outdoor offerings of St Johnsbury while protecting your skin from harmful ultraviolet rays.
As the sun rises, the UV Index starts its ascent, with a gentle 1 at 07:00. By 08:00, it begins to climb, reaching 2, signaling a reminder to take care. The real intensity kicks in at 10:00, where the index peaks at 6, escalating to a scorching 9 by noon. The hottest moment arrives at 13:00, showcasing a dramatic 10—a level that demands serious sun protection. Although the UV level begins to drop after this peak, it remains notable; at 14:00, it settles at 9, then declines gently, hitting 3 by 17:00. As daylight fades towards the evening, it tapers off to 2 at 18:00 and finally returns to a safe 1 by 19:00. It's a vivid reminder of the sun's power throughout the day!
| 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 | 10 | 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 noticeable fluctuations, impacting the risk of skin damage due to sun exposure. High-risk months are primarily from April to August, where the UV Index reaches very high levels of 8 to 10, necessitating caution with a significantly reduced burn time of just 15 minutes. In contrast, the UV levels are much lower from January to March and again from November to December, characterized by low to moderate exposure with burn times extending up to 45 minutes. Residents and visitors should be particularly mindful during the peak summer months, ensuring adequate sun protection such as sunscreen, hats, and clothing, and seeking shade during the day to minimize the risk of skin damage. Remember, smarter sun habits can help you enjoy the outdoors safely!
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| St Johnsbury | 2 | 4 | 5 | 8 | 9 | 10 | 9 | 9 | 7 | 5 | 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 |