Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Sioux Falls, as it serves as a vital tool for protecting your skin from the harmful effects of ultraviolet radiation. With typical summer days bringing high UV levels, especially around noon when the index can soar to 11, being aware of these levels can help prevent painful sunburns and long-term skin health issues. Sioux Falls experiences a Dfa climate, characterized by warm summers, which increases exposure risks throughout the day. By staying informed about the UV Index, you can enjoy the beautiful outdoors while safeguarding your skin!
The UV Index shows a dramatic rise as the morning unfolds, starting at a low of 1 at 07:00. By 08:00, it gently climbs to 2, and by 09:00, it reaches 3. The mid-morning reveals a surge, peaking at 5 by 10:00. As the sun reaches its zenith, the UVI soars to a staggering 10 at noon, with a climb to 11 at 13:00, marking the highest point of the day. Just after, it gradually dips, but remains considerable at 10 by 14:00 and 9 at 15:00. The afternoon sees a striking decrease to 7 at 16:00 and continues to fall, landing at 3 by 18:00, before tapering off to 1 by 19:00. It's a clear reminder to stay sun-safe 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 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV levels exhibit significant seasonal changes, with the most intense exposure occurring during the summer months. January and December have the lowest UV Index values (2), indicating low risk for sunburn, while February and March present a moderate risk with an index of 5. High-risk months include April through September, where UV Index values peak at 11 in June, categorizing it as extreme exposure. During these peak months, residents and visitors are advised to practice sun safety by seeking shade, wearing protective clothing, and applying sunscreen frequently, especially between 10 AM and 4 PM when UV rays are strongest. As the UV levels decrease in October and November, precautions can be relaxed, but maintaining a moderate level of awareness remains essential.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sioux Falls | 2 | 5 | 5 | 8 | 9 | 11 | 10 | 9 | 8 | 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 |