Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Uto, Japan, where the climate is classified as Cfa, characterized by humid summers and mild winters. Knowing the daily UV levels is essential for effective sunburn prevention and maintaining skin health, as exposure to high UV radiation can lead to serious skin issues. With midday UV Index levels peaking at a striking 12, it's important to recognize the risks, especially during the sunniest hours. Being informed enables you to enjoy outdoor activities safely while protecting your skin from potential damage!
The UV Index begins its rise at 7:00 AM with a low of 2, gradually climbing to a moderate 3 by 8:00 AM. By 9:00 AM, it reaches 6, but it's at 10:00 AM when the sun truly bears down, peaking at a high of 9. The intensity continues to soar, hitting a maximum of 12 at 12:00 PM, making it the most UV-active hour of the day. From there, it subtly declines, dropping back to 11 at 1:00 PM, and 9 at 2:00 PM. The afternoon brings relief as the index falls to 6 by 3:00 PM and continues to decrease, settling at 4 by 4:00 PM. As the day winds down, the UV Index dips to 2 by 5:00 PM and further to a safe 1 by 6:00 PM and stays consistent through 7:00 PM. Stay sun-smart and avoid peak UV hours for your skin's safety!
Time | UVI | Category | Time to Burn |
---|---|---|---|
07:00 | 2 | low | 45 min |
08:00 | 3 | moderate | 30 min |
09:00 | 6 | high | 25 min |
10:00 | 9 | very high | 15 min |
11:00 | 11 | extreme | 10 min |
12:00 | 12 | extreme | 10 min |
13:00 | 11 | extreme | 10 min |
14:00 | 9 | very high | 15 min |
15:00 | 6 | high | 25 min |
16:00 | 4 | moderate | 30 min |
17:00 | 2 | low | 45 min |
18:00 | 1 | low | 45 min |
19:00 | 1 | low | 45 min |
Throughout the year, the UV Index shows notable seasonal changes, with the highest risk occurring from March to September. During these months, the index reaches extreme levels, particularly peaking in August with a UV Index of 13. Visitors and residents should exercise caution during high-risk months and, ideally, limit direct sun exposure to less than 10 minutes daily between April and September. In contrast, the UV Index is relatively moderate in January and December, with burn times of 30 minutes. To minimize the risk of skin damage, it is essential to apply sunscreen, wear protective clothing, and seek shade, especially during peak hours from late morning to early afternoon.
UV Risk Categories
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Sapporo UVI | 2 | 3 | 6 | 7 | 9 | 9 | 9 | 10 | 8 | 5 | 3 | 2 |
Yokohama UVI | 3 | 5 | 8 | 9 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 4 |
Tokyo UVI | 3 | 5 | 8 | 9 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 4 |
Nagoya UVI | 4 | 6 | 8 | 10 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 3 |
Osaka UVI | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |
Uto | 5 | 6 | 9 | 11 | 12 | 12 | 12 | 13 | 11 | 8 | 6 | 4 |