Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Greenfield, United States, as it plays a vital role in protecting your skin against harmful ultraviolet (UV) radiation. Knowledge of UV levels is essential for sunburn prevention and maintaining overall skin health, especially during the peak hours when the sun's intensity reaches its maximum, with indices soaring as high as 10 around midday. With Greenfield's Cfa climate, characterized by warm summers, residents face increased risks of UV exposure, highlighting the importance of being informed and prepared to enjoy the outdoors safely. Stay vigilant and make educated choices to safeguard your skin against the sun!
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 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 8 | very high | 15 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 notable seasonal fluctuations, which are particularly prominent in the spring and summer months. High-risk months for UV exposure include April through August, with the index peaking in June and July at 11, categorized as extreme exposure, where the burn time is a mere 10 minutes. As the summer wanes into fall, the UV Index gradually declines, with October reflecting a high category and increased burn times of 25 minutes. Residents and visitors should take precautions during the high-risk months, such as applying broad-spectrum sunscreen, wearing protective clothing, and seeking shade during peak hours to minimize the risk of 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 |
| Greenfield | 3 | 5 | 6 | 9 | 10 | 11 | 11 | 9 | 9 | 6 | 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 |