Last updated: July 2, 2025
In Knoxville, United States, awareness of the UV Index is crucial for safeguarding your skin against harmful ultraviolet radiation. Understanding UV levels is not just about avoiding sunburns; it's vital for long-term skin health and preventing serious conditions like skin cancer. With Knoxville's Cfa climate, featuring warm summers and ample sunshine, the risks of high UV exposure, especially around midday when the index peaks at a scorching 11, become especially relevant. By staying informed about the UV Index, residents can enjoy the outdoors while protecting their skin from damage.
Today's UV Index presents a dynamic landscape of sun exposure. The day begins with a mild index of 1 at 7:00 AM and 8:00 AM, ideal for enjoying a morning stroll. As the sun ascends, we hit 2 by 9:00 AM, before a significant leap to 5 at 10:00 AM. The intensity peaks dramatically at 12:00 PM, marked with a dazzling 10, then soars to an impressive 11 from 1:00 PM to 2:00 PM. As we transition into the afternoon, a gradual decline ensues, dropping to 8 at 4:00 PM, followed by 5 at 5:00 PM, then a gentle descent to 3 by 6:00 PM. The evening settles back to a 1 by 7:00 PM. Stay sun safe! Remember to protect your skin during the peak hours of UV exposure!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 8 | very high | 15 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 1 | low | 45 min |
The UV Index exhibits significant seasonal variation, peaking during the summer months. From January (UV Index 4) to February (UV Index 7), exposure remains moderate to high, with burn times shortening as spring approaches. The months of March and April see a sharp increase in UV levels (9 and 10 respectively), indicating very high risk for sunburn, with a burn time of just 15 minutes. The extreme category dominates from May to August (UV Index 11), where even brief sun exposure can result in burns within 10 minutes. As we move into September and October, the index drops to 10 and 8, maintaining a very high risk, before returning to a moderate level in November and December (UV Index 6 and 4). Visitors and residents are strongly advised to take precautions, especially from March through October, by wearing protective clothing, using sunscreen, and seeking shade during peak sun 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 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Knoxville | 4 | 7 | 9 | 10 | 11 | 11 | 11 | 11 | 10 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |