Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Northfield, United States, especially given the region's Dfb climate which offers distinct seasonal variations and potential for increased UV exposure during warmer months. Awareness of UV levels helps in effectively preventing sunburn and maintaining healthy skin, as even moderate exposure can lead to long-term damage. With peak UV Index readings reaching as high as 9 around noon, it's essential to stay informed and take precautions against harmful rays, ensuring you enjoy the beautiful outdoor spaces of Northfield while keeping your skin safe.
The UV Index reveals a dynamic pattern throughout the day, starting at a mild 1 at 07:00 and steadily rising as the sun reaches its peak. By 10:00, it escalates to a moderate 6, reaching 8 at 11:00 and peaking at an intense 9 from 12:00 to 13:00. This period signifies the greatest caution for sun exposure, making it essential to seek shade and wear protective clothing. As the afternoon unfolds, the index begins to dip, dropping to 8 at 14:00, then declining further to 7 by 15:00, and tapering down to 1 by 19:00. Overall, it’s a day that encourages sun safety awareness, particularly during the midday hours when UV radiation is at its strongest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 5 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, the UV Index reveals significant fluctuations in sun exposure risk. Winter months (January and February) have moderate UV levels with an index of 3 to 4, leading to a burn time of approximately 30 minutes. Transitioning into spring, the UV Index rises sharply: March reaches a high of 6, and by April it soars to 8, signaling the start of very high risk months with a burn time reduced to 15 minutes. The summer months (May through August) maintain this high threat level, peaking at 10 in June, necessitating extra precautions for outdoor activities. As September and October approach, the UV Index decreases to 7 and 6, respectively, still indicating a high risk for 25 minutes of safe sun exposure. November and December see a return to moderate and low levels for UV exposure, with longer burn times of 30 to 45 minutes. Residents and visitors are advised to take protective measures, especially from April to August, including wearing sunscreen, protective clothing, and limiting time in direct sunlight during peak hours.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Northfield | 3 | 4 | 6 | 8 | 9 | 10 | 9 | 9 | 7 | 6 | 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 |