Last updated: June 2, 2025
In Colby, United States, understanding the UV Index is essential for maintaining your skin health and preventing sunburn. As this charming locale experiences a Dfb climate with varying seasonal temperatures, residents and visitors face distinct UV exposure risks throughout the year. With UV levels soaring to a peak of 10 around midday, knowing when to seek shade or apply sunscreen can make all the difference in protecting your skin from harmful rays. Staying informed about the UV Index empowers you to enjoy the outdoors safely while safeguarding against short-term discomfort and long-term health issues.
The UV Index throughout the day shows a clear progression in intensity, peaking at a formidable 10 around noon. The morning starts off relatively mild, with values of 1 at 7:00 AM gradually rising to 4 by 9:00 AM. As the day unfolds, the index escalates swiftly, reaching 8 by 11:00 AM and then hitting its zenith of 10 at 12:00 PM and 1:00 PM. After this peak, there’s a noticeable decline; by 3:00 PM, it drops to 8 and continues to decrease until it settles back at 1 by 7:00 PM. This data underscores the importance of sun protection during the peak hours of 11:00 AM to 1:00 PM, when UV exposure is 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 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index levels fluctuate significantly, indicating varying risks of skin damage from sun exposure. The low-risk months are January and December, with UV Index levels of 2, allowing for about 45 minutes of safe sun exposure. As we move into early spring, February and March show a moderate index of 4 and 5, respectively, reducing burn time to 30 minutes. The high-risk months notably occur from April to August, peaking in June with a UV Index of 10, and requiring sunscreen application and minimal exposure after just 15 minutes. September dips to a high level of 7, while October and November present a moderate risk. Visitors and residents should take precautions, particularly during peak summer months by seeking shade, wearing protective clothing, and using sunscreen to minimize skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Colby | 2 | 4 | 5 | 7 | 8 | 10 | 9 | 9 | 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 |