Last updated: July 2, 2025
Understanding the UV Index is crucial for residents of Story City, United States, as it serves as a vital tool in promoting sunburn prevention and maintaining skin health. High UV levels, particularly during the peak afternoon hours, can significantly increase the risk of skin damage, making awareness essential for outdoor activities. Story City's humid continental climate (Dfa) brings its own set of challenges, with summer months often seeing elevated UV exposure. By staying informed about the daily UV Index, you can protect yourself and your loved ones from harmful rays while enjoying the beautiful sunny days that Story City has to offer.
The UV Index reveals a dynamic ascent and descent throughout the day, peaking with intensity during midday. Starting at a gentle 1 at 7:00 AM, it climbs steadily, reaching 10 by 1:00 PM and maintaining this highest level until 2:00 PM. This critical window indicates significant sun exposure, and it’s essential to take precautions. As the afternoon progresses, the index begins to taper off, dropping to 8 at 3:00 PM, then gradually falling to 1 by 7:00 PM. This data highlights the importance of being sun-smart during the peak hours to minimize UV exposure risks.
| 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 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | 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 undergoes notable seasonal changes, with the highest levels typically occurring in the summer months. April signals the onset of increased UV radiation, peaking in June with an extreme UV Index of 11 and a burn time of just 10 minutes. The high-risk months for sun exposure are April to September, when values range from 8 to 11, indicating very high to extreme levels. Residents and visitors should be especially cautious during this period, taking proactive measures such as wearing sunscreen, sunglasses, and protective clothing, and seeking shade during peak sunlight hours. In contrast, the winter months of December and January present a moderate UV risk, but vigilance remains essential, as skin can still be affected by UV rays even when temperatures are cooler.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 |
| Story City | 3 | 5 | 5 | 8 | 9 | 11 | 10 | 9 | 8 | 6 | 3 | 3 |
| 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 |