Last updated: August 1, 2025
In Black River Falls, Wisconsin, being aware of the UV Index is crucial for protecting your skin from the sun's harmful rays. Understanding UV levels not only helps in preventing painful sunburns but also plays a significant role in maintaining long-term skin health. Given the area's Dfb climate, Black River Falls experiences varying UV exposure throughout the day, peaking at a high level of 10 around noon. This makes it essential for residents and visitors alike to stay informed about UV levels, especially during the warmer months when the sun's intensity is at its greatest. Remember, a little awareness can go a long way in safeguarding your skin!
As the day unfolds, the UV Index climbs steadily, peaking at an impressive 10 between 1 PM and 2 PM, marking the sun's intensity at its highest. Starting at a mild 1 at 7 AM, the index gradually rises, reaching 9 by noon and hitting 8 at 11 AM. The afternoon witnesses a slight dip, with values dropping to 7 by 3 PM and trailing off into lighter levels of 5 and 3 later in the day. By 7 PM, the UV Index returns to a soft 1, signaling the end of a sun-drenched day. It's essential to stay sun-safe during the peak hours, especially between 11 AM and 2 PM, when UV exposure can be most harmful.
| 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 | 8 | 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, UV Index levels undergo significant changes, with notable increases during the warmer months. January and December experience low UV exposure (Index 2), allowing for longer burn times of 45 minutes. However, as early as February, the index rises to 4, indicating a moderate risk with a burn time of 30 minutes. The high-risk months peak from April to August, with UV Index values reaching 8 to 10 and a burn time as brief as 15 minutes—these months are categorized as very high risk for sunburn. In September, UV exposure decreases slightly to a 7, still classified as high risk, necessitating caution with a burn time of 25 minutes. As temperatures drop in October and November, the index falls back to moderate levels, allowing for burn times of 30 minutes. It is crucial for both visitors and residents to take protective measures—such as wearing sunscreen, protective clothing, and seeking shade—particularly during the April to August period, when the risk of skin damage from UV exposure is at its highest.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Black River Falls | 2 | 4 | 5 | 8 | 8 | 10 | 10 | 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 |