Last updated: May 3, 2025
Living in Tsuno, Japan means enjoying a beautiful climate, but it also comes with the responsibility of being aware of the UV Index. Understanding UV levels is crucial for sunburn prevention and maintaining overall skin health, especially during the summer months when exposure can peak with a maximum index of 12 around noon. In this Cfa climate zone, where sunny days are plentiful, the risk of harmful UV radiation is significant—especially during mid-day hours. Stay informed and protect your skin by keeping track of the UV Index, ensuring you enjoy the outdoors safely!
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 |
As the seasons change, so do the UV index levels, significantly affecting sun exposure and safety. Throughout the year, high-risk months generally occur from March to September, where the UV index peaks at 12, classified as extreme exposure, particularly during May through August. During these months, burn time is as short as 10 minutes, necessitating vigilant sun protection measures. Visitors and residents are urged to use sunscreen, wear protective clothing, and seek shade during peak hours to mitigate the risk of skin damage. In contrast, the UV index is lower in January, February, October, and November, where exposure is categorized as moderate to high; however, sunscreen remains advisable during all months to ensure skin health year-round.
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 |
| Tsuno | 5 | 6 | 9 | 10 | 12 | 12 | 12 | 12 | 11 | 8 | 6 | 4 |