Last updated: July 2, 2025
In Alliance, United States, staying informed about the UV Index is essential for safeguarding your skin health. Understanding UV levels helps you protect against harmful sunburns, ensuring your time outdoors is not only enjoyable but also safe. With a Cfa climate that typically features sunny summers and varying UV exposure risks throughout the day, knowing when to seek shade or apply sunscreen is crucial. For instance, during peak hours from 11 AM to 2 PM, the UV Index can soar to levels as high as 11, indicating the need for extra caution. By being aware of the UV Index, you can take the necessary precautions to enjoy the sun while minimizing the risk of skin damage.
The UV Index throughout the day presents a clear trajectory of increasing intensity, peaking dramatically as the sun reaches its zenith. At 07:00, the index starts modestly at 1, signifying minimal risk. However, as the hours roll on, from 08:00 to 10:00, it climbs steadily to 6, marking the onset of moderate exposure. The real surge occurs between 11:00 and 13:00, where the index hits a staggering 11, indicating a very high risk for unprotected skin. Even as it begins to taper off in the afternoon—returning to 9 by 15:00 and further down to 4 by 17:00—the day's UV intensity serves as a reminder of the importance of sun protection. By 19:00, it drops back to a safe 1, allowing for a sigh of relief as daylight wanes. Embrace the sun wisely!
| 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 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 9 | 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 |
The UV Index experiences significant seasonal variations, with the most dangerous months for sun exposure falling between March and August. During this period, UV levels peak at 11 in May, June, and July, indicating an extreme risk of harm from unprotected sun exposure, where burn time can be as short as 10 minutes. Residents and visitors should take extra precautions during these months, such as wearing protective clothing, seeking shade, and applying broad-spectrum sunscreen regularly. As the year progresses into the fall and winter months, the UV Index decreases, reaching moderate levels in January and December, with a burn time of 30 minutes. However, even in these months, some sun protection is advisable.
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 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Alliance | 4 | 6 | 8 | 10 | 11 | 11 | 11 | 10 | 9 | 8 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |