Last updated: May 3, 2025
Understanding the UV Index in Iowa City is essential for maintaining skin health and preventing sunburn. Given the city's Dfa climate, residents and visitors alike must be vigilant about UV exposure, especially when values peak at 9 during midday hours. With significant UV levels between 10 AM and 2 PM, knowing when to seek shade or apply sunscreen can make a critical difference in protecting your skin. Awareness of the UV Index not only helps mitigate immediate risks like sunburn but also contributes to long-term skin health, making it a vital part of outdoor planning in Iowa City.
The UV Index for the day showcases a notable rise in intensity as the sun climbs higher in the sky. Starting at a low of 1 at 7:00 AM, the index gradually increases to a moderate level of 3 by 9:00 AM. However, from 10:00 AM onward, things heat up significantly, peaking at a scorching 9 from noon to 2:00 PM. As the afternoon progresses, the UV Index gradually dips back to a friendly 3 by 5:00 PM, then descends further to 1 by the time evening sets in. This pattern underscores the importance of sun protection during peak hours, especially between 11:00 AM and 2:00 PM, when UV levels are at their highest.
| 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 | 9 | 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 | 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 fluctuate significantly, impacting sun exposure and potential skin damage. The high-risk months, identified by an increased UV Index, are April through August, where levels reach a concerning 8 to 11, categorized as either very high to extreme. Notably, June exhibits the peak UV Index of 11, necessitating vigilant sun protection. Residents and visitors are advised to minimize sun exposure during these months, seeking shade and applying broad-spectrum sunscreen regularly, especially during peak hours. In contrast, winter months like January, November, and December present a moderate risk with an UV Index of 3 to 4, allowing for more lenient outdoor activities while still practicing sun safety.
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 |
| Iowa City | 3 | 5 | 6 | 8 | 9 | 11 | 10 | 9 | 8 | 6 | 4 | 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 |