Last updated: May 3, 2025
Understanding the UV Index is essential for residents of Yankton, United States, where the climate can lead to varying UV exposure throughout the year. With peak UV levels reaching 9 during midday, being aware of these values is crucial for sunburn prevention and long-term skin health. By grasping how to interpret the UV Index, you can take proactive steps to protect your skin from harmful rays, especially in the summer months when the sun is at its strongest. Given Yankton’s humid continental climate, it's vital to stay informed about UV risks to enjoy the outdoors safely while minimizing the chances of sun damage.
As the sun rises, the UV Index begins at a low 1 at 07:00, providing a gentle start to the day. By 09:00, it picks up to 3, signaling the need for a bit more awareness. The real warmth comes at 10:00, with the index reaching 5, and it escalates quickly as noon approaches. By 12:00, we hit 8, and at 13:00, the UV index peaks at 9, marking the height of solar intensity. As the afternoon progresses, values remain high but start to dip slightly: 8 at 15:00 and then down to 6 by 16:00. As the sun begins to set, the index falls to 4 at 17:00 and finally drops back to 1 by evening, reminding us to bask in the sun wisely and protect our skin during peak hours!
| 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 | 8 | very high | 15 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, the UV Index exhibits notable seasonal fluctuations, peaking during the summer months. From January to April, the index gradually rises from 3 to 8, indicating a shift from moderate to very high risk. The risk of harm significantly increases in May and reaches its zenith in June with an extreme index of 11. High-risk months include March (UV Index 6) and April (UV Index 8), transitioning to very high risks from May through September when the index remains above 8. During these peak months, particularly in June, visitors and residents are strongly advised to take precautions: seek shade, wear protective clothing, and apply sunscreen regularly to mitigate skin damage. As the year progresses towards October and November, the UV Index decreases, returning to moderate levels by December, where exposure risks are lower and burn time increases to 45 minutes. This seasonal insight highlights the importance of adjusting sun safety practices throughout the year.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Yankton | 3 | 5 | 6 | 8 | 9 | 11 | 10 | 10 | 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 |