Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Madison, United States, where sunny days can lead to both beautiful vistas and significant sun exposure. With the UV levels peaking at 10 during midday, knowledge of these indices helps in preventing sunburn and protecting skin health. Madison's Cfa climate presents its own challenges, with warm summers amplifying UV radiation risks. By staying informed about the UV Index, you can enjoy the outdoors while ensuring you and your loved ones are safeguarded against harmful effects of the sun.
At dawn, 7:00 AM, the UV Index is a mild 1, offering a gentle start to the day. As the sun climbs higher, it steadily rises, reaching 2 by 8:00 AM and hitting 3 at 9:00 AM. However, between 10:00 AM and 1:00 PM, the intensity increases sharply, peaking at an impressive 10 from 12:00 PM to 1:00 PM—the highest level of risk. The UV Index then begins its descent, dropping to 8 at 3:00 PM, followed by a gradual decline to 4 by 5:00 PM. As evening approaches, the index wanes further, settling back down to 1 by 7:00 PM. To enjoy the sunshine while staying safe, make sure to take precautions, especially during those peak 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 | 8 | very high | 15 min |
| 12:00 | 10 | 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 |
As the seasons change, so do the UV Index levels, which significantly affect sun exposure risk. From January's moderate UV Index of 4, which allows for a 30-minute burn time, to June's extreme peak of 11, where unsafe exposure can lead to a burn in just 10 minutes, the months of March through October represent the highest risk periods. Specifically, April, May, June, July, August, and September showcase very high to extreme levels, with June posing the greatest danger. It’s imperative for residents and visitors to take precautions during these months. Sunscreen application, protective clothing, and limiting exposure times, especially during midday when the sun is strongest, are vital measures for staying safe from UV-related harm. As autumn approaches, UV levels retreat but remain notable, reminding everyone to remain vigilant even as the temperatures cool.
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 |
| Madison | 4 | 6 | 8 | 9 | 10 | 11 | 10 | 10 | 9 | 8 | 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 |