Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Cook, United States, where exposure to harmful ultraviolet rays can pose significant risks to skin health. Being aware of local UV levels allows you to take proactive measures against sunburn and long-term skin damage. In Cook's Dfb climate, marked by warm summers and cold winters, UV exposure can vary considerably. From midday hours when the UV Index peaks at an intense level of 8, it’s essential to stay informed and protected. This means wearing sunscreen, hats, and protective clothing, especially during those high-risk hours. Prioritizing UV awareness will help you enjoy the outdoors while safeguarding your skin!
The UV Index throughout the day presents a dynamic landscape of sun exposure. Starting off at a mild 1 at 7:00 AM, the intensity gradually rises, hitting 2 by 8:00 AM and 3 by 9:00 AM. The real peak emerges at 12:00 PM and 1:00 PM, where it reaches a robust 8—a signal to seek shade and cover up! As the afternoon progresses, the index gently declines to 6 by 3:00 PM, before tapering off further to 2 by 6:00 PM, and finally returning to a cool 1 by 7:00 PM. This data reminds us to be sun-smart during those critical midday hours!
| 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 | 6 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 6 | 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, the UV Index experiences significant seasonal changes, impacting sun exposure and burn times. January and December see low UV levels (Index 2), with burn times of 45 minutes, while February and November moderate (Index 3), reducing burn time to 30 minutes. As spring arrives, March (Index 5) indicates a moderate risk before transitioning to April's high level (Index 7) with a burn time of 25 minutes. The peak risk occurs in May and June, where the UV Index reaches 8 to 9, categorizing exposure as very high and necessitating protective measures within just 15 minutes of sun exposure. July continues this trend, while August sees a slight decrease to 8. The UV Index tapers off in September (Index 7), October (Index 5), and November (Index 3), before returning to low levels in December. Visitors and residents are advised to take extra precautions during May through August, including wearing protective clothing, applying sunscreen, and seeking shade during peak hours to minimize the risk of UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cook | 2 | 3 | 5 | 7 | 8 | 9 | 9 | 8 | 7 | 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 |