Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Sioux Falls, where the climate is characterized by its distinct seasons and varying sun exposure throughout the year. With peak UV levels reaching 9 during the midday hours, awareness of these fluctuations is essential for preventing sunburn and promoting long-term skin health. As the sun's intensity increases, so does the risk of harmful skin damage, making it vital for residents to stay informed and take appropriate precautions. Whether planning outdoor activities or simply enjoying the beautiful South Dakota skies, keeping an eye on the UV Index can help you make safer choices under the sun.
During the early hours of the day, the UV Index remains low, peaking at 1 until 9:00 AM. As the sun rises higher, the index climbs to 5 by 10:00 AM and reaches a maximum of 9 between 1:00 PM and 2:00 PM, indicating a strong need for sun protection during these peak hours. Afterward, the UV Index gradually declines, dropping to 4 at 5:00 PM and falling back to 1 by 7:00 PM. It’s essential to stay vigilant during the midday hours when the sun is at its strongest, and remember to apply sunscreen to enjoy the outdoors safely!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | 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 | 9 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 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 |