Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Joanna, United States, where sun exposure can significantly impact skin health. The UV Index measures the strength of ultraviolet rays on a scale that helps you gauge how much protection you need throughout the day. With a typical climate classified as Cfa, Joanna experiences heightened UV levels, particularly around midday, when values can reach as high as 11. This makes awareness essential to prevent sunburn and long-term skin damage. By understanding local UV levels, you can make informed decisions about sun protection and enjoy the outdoors safely.
The UV Index undergoes a dramatic rise throughout the day, starting from a gentle 1 at 07:00 and gradually climbing to a peak of 11 by 13:00. As the sun reaches its zenith, UV exposure intensifies, with values soaring to 9 at noon and tapering off through the afternoon. By 15:00, the index begins to decline, slipping back to 6 by 16:00, and down to a safe 1 by 19:00. This data highlights the importance of sun protection during peak hours, especially between 10:00 and 15:00, when the UV Index is at its most potent.
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 | 9 | very high | 15 min |
13:00 | 11 | extreme | 10 min |
14:00 | 10 | very high | 15 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 |
As the seasons change, the UV Index demonstrates considerable variation, impacting burn potential and risk levels for skin exposure. The highest risk months occur from March to August, with values peaking at 11 during May, June, and July, indicating an extreme exposure category with a burn time of just 10 minutes. February marks a shift into a high risk category, while September through November gradually decreases the UV levels, transitioning back to moderate by December. It is crucial for visitors and residents alike to exercise caution during these high-risk months by wearing protective clothing, applying sunscreen regularly, and seeking shade to mitigate the potential for 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 |
Joanna | 4 | 7 | 8 | 10 | 11 | 11 | 11 | 10 | 9 | 8 | 6 | 4 |
Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |