Last updated: August 1, 2025
Understanding the UV Index in Northfield, United States, is crucial for protecting your skin and overall health. With the climate categorized as Cfa, residents face varying UV exposure levels throughout the day, peaking between 11:00 AM and 1:00 PM. Awareness of these levels is essential for preventing sunburn and long-term skin damage. On sunny days, UV levels can rise to as high as 10, highlighting the importance of sun safety measures. By staying informed about the UV Index, Northfield residents can enjoy the outdoors while safeguarding their skin against harmful ultraviolet rays.
The UV Index throughout the day showcases a dynamic pattern of sun exposure, peaking during the afternoon. At 07:00, the index starts low at 1, gradually increasing as the sun rises. By 10:00, it reaches 6, signaling a rise in sun intensity, culminating in a striking 10 from 12:00 to 13:00, indicating a high risk of harm from unprotected sun exposure. As the day progresses, the UV Index declines, dropping to 3 by 17:00, and steadily returning to 1 by 19:00. This data highlights the importance of sun protection, especially during midday when the UV Index is at its 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 | 10 | 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 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index levels exhibit notable seasonal variations that can significantly impact sun exposure. January and December have moderate UV conditions (Index 3), allowing for a 30-minute burn time, while February shows a slight increase to Index 5, maintaining a burn time of 30 minutes. As spring approaches, March reaches an elevated Index of 6, indicating high risk with a reduced burn time of 25 minutes. The risk peaks during the summer months—April through August—where the Index consistently hits 9 or 10, categorizing these months as very high risk for UV exposure, necessitating only 15 minutes of sun exposure before burning occurs. The risk diminishes slightly in September (Index 8) and October (Index 7) but remains significant, with shorter burn times of 15 and 25 minutes, respectively. November and December revert to moderate levels (Index 4 and 3). Visitors and residents are advised to take precautions during the high-risk months, particularly from April to September, by seeking shade, wearing protective clothing, and applying sunscreen to minimize the risk of UV-related skin damage.
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 |
| Northfield | 3 | 5 | 6 | 9 | 10 | 10 | 10 | 10 | 8 | 7 | 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 |