Last updated: June 2, 2025
In Thief River Falls, understanding the UV Index is essential for safeguarding your skin against the sun's harmful rays. As a resident of this Dfb climate zone, you're likely to experience varying UV levels throughout the day. Recognizing these levels aids in preventing sunburn and promoting long-term skin health. With peak UV readings soaring to 9 between noon and 2 PM, it’s crucial to stay informed and take protective measures. Whether you’re enjoying outdoor activities or simply soaking up the sun, being UV-aware can make a significant difference in your overall well-being.
Throughout the day, the UV Index fluctuates dramatically, peaking during the midday hours. Starting at a low of 1 at 07:00, the index rises steadily, reaching 3 by 09:00. As 10:00 approaches, it escalates to 5, but the real intensity hits between 12:00 and 14:00 when it peaks at 9. During this window, it's crucial to take sun safety precautions. As the afternoon progresses, the UV levels begin to taper off, dropping to 8 at 15:00 and gradually declining further to 3 by 18:00. Finally, the UV Index returns to its morning low of 1 by 19:00, marking a safe end to sun exposure for the day.
| 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 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so does the UV Index, which is crucial for understanding sun exposure risks. From January to February, the UV Index starts low at 2, indicating a minimal risk of harm, but it gradually rises to 3 in February, marking a moderate exposure category with a burn time of 30 minutes. The risk intensifies significantly from March to August, peaking at 9 during June and July, where the burn time reduces to just 15 minutes under very high risk. May and August also remain dangerous with an 8 rating. As fall approaches, the UV levels drop, presenting a high risk of 7 in September, then decrease again to moderate and low levels by October through December. Visitors and residents are advised to protect themselves during high-risk months, particularly from late spring through summer, by wearing sunscreen, protective clothing, and seeking shade whenever possible, as sun exposure can lead to serious skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thief River Falls | 2 | 3 | 5 | 6 | 8 | 9 | 9 | 8 | 7 | 4 | 2 | 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 |