Last updated: August 1, 2025
In Deerfield, United States, being aware of the UV Index is crucial for protecting your skin and overall health. As the sun's harmful rays can lead to sunburn and long-term skin issues, understanding these UV levels allows residents to take necessary precautions and enjoy outdoor activities safely. With a BSk climate, Deerfield experiences varying levels of UV exposure, peaking at a significant 11 during midday hours. Staying informed about the UV Index helps ensure you can enjoy the sun while minimizing health risks.
Throughout the day, the UV Index experiences a notable rise, peaking at 11 between 1:00 PM and 2:00 PM, indicating an intense level of ultraviolet radiation. Starting off with a mild 1 at 7:00 AM and 8:00 AM, the index gradually climbs to 2 by 9:00 AM. As the sun reaches its zenith, the index skyrockets to 9 at 12:00 PM and continues to intensify, hitting its maximum of 11 in the early afternoon. After this peak, the UV Index begins to taper off, dropping to 6 by 5:00 PM and concluding the day at a more manageable 2 by 7:00 PM. It's essential to stay protected during those high exposure hours from 11 AM to 3 PM!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 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, the UV Index experiences significant fluctuations, impacting sun safety for both visitors and residents. From January to February, the UV Index remains moderate (4-5), with a burn time of 30 minutes. As spring approaches, March marks a transition to a high UV Index of 7, and by April, it escalates to 10, signaling the start of very high risk months. The peak UV exposure occurs in May and June, reaching an extreme 11-12, where one can burn in just 10 minutes. July continues this pattern, but a slight decline begins in August (UV Index 11). By September, the UV Index drops to 9, still indicating very high risk, before settling back to high levels in October (UV Index 7). During the late fall and winter months, the index decreases to moderate levels again. Visitors and residents are strongly advised to take precautions, especially from April to August, ensuring proper sun protection such as wearing sunscreen, protective clothing, and seeking shade during peak hours to minimize the risk of UV-related harm.
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 |
| Deerfield | 4 | 5 | 7 | 10 | 11 | 12 | 12 | 11 | 9 | 7 | 5 | 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 |