Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Louisville, United States, where sun exposure can be intense, especially during the warmer months. With UV levels frequently peaking around 11, becoming aware of UV risks not only helps prevent painful sunburns but also plays a vital role in maintaining overall skin health. Louisville's Cfa climate features humid summers that can elevate UV exposure risks, making it essential for locals to stay informed and protect themselves during peak sun hours, particularly around noon.
The UV Index throughout the day paints a vivid picture of sun intensity and its impact on outdoor activities. Starting early at 7:00 AM, the exposure remains low at a mere 1, ideal for morning strolls. As the sun climbs, 9:00 AM sees a slight increase to 3, hinting at the day's potential. By 10:00 AM, the index escalates to 5, and it reaches a peak at 12:00 PM with a blistering 10. The highest point occurs around 1:00 PM and 2:00 PM, where it hits 11, indicating the need for sun protection. Gradually, the index begins to decline, drifting down to 7 by 4:00 PM, and dropping to a safe 1 by 7:00 PM, closing the day with a protective embrace as twilight falls. This information serves as a crucial guide for planning sun-safe activities!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 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 | 9 | very high | 15 min |
| 16:00 | 7 | 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 exhibit noteworthy seasonal changes, with high-risk months identified from March to August, when exposure reaches very high or extreme levels. In March and April, the UV Index peaks at 9 and 10, respectively, indicating a transition into the more hazardous summer months. May through August experience the highest UV Index of 11, categorized as extreme, which necessitates diligent sun protection within a burn time of just 10 minutes. As September and October arrive, UV levels remain considerable, with a very high index of 9 and 8, and slowly tapering off towards the end of the year. It is crucial for both visitors and residents to take appropriate precautions during these months, such as wearing sunscreen, protective clothing, and seeking shade during peak hours 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 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Louisville | 4 | 7 | 9 | 10 | 11 | 11 | 11 | 11 | 9 | 8 | 6 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |