Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Yachiyo, Japan, where UV exposure can pose significant health risks, especially during the warmer months. With peak values reaching as high as 10 around midday, it’s important to be aware of the UV levels to prevent sunburn and protect your skin health. The climate in Yachiyo, classified as Cfa, brings high humidity and ample sunshine, making the need for UV awareness even more pressing. By staying informed about daily UV levels, you can enjoy the outdoors safely while minimizing skin damage and reducing the risk of skin-related health issues.
The UV Index shows a significant rise from 2 at 07:00 to a peak of 10 at 11:00 and 12:00, indicating the sun’s intensity is at its highest during these hours. As the day progresses, the index gradually declines, falling to 7 by 14:00 and dropping to 4 by 15:00. By late afternoon and evening, the UV exposure diminishes further, reaching 1 at 17:00 and 18:00, before tapering off to 0 by 19:00. This data emphasizes the importance of sun protection during the midday hours, particularly between 10:00 and 14:00, when UV radiation is most potent. Enjoy the sun responsibly!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 5 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 7 | high | 25 min |
| 15:00 | 4 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The seasonal UV variations indicate a significant increase in UV exposure from winter to summer, with high-risk months emerging from April through August. During this period, the UV Index peaks at 11 (extreme), particularly in June, July, and August, where the burn time drops to just 10 minutes. Visitors and residents are advised to take precautionary measures during these months, such as seeking shade, wearing protective clothing, and applying sunscreen frequently. As the UV levels decrease in the fall and winter months, with indices dropping to 3 in January and December, the risk of sunburn diminishes. However, maintaining sun safety practices year-round remains essential for health and well-being.
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 |
| Yachiyo | 3 | 5 | 7 | 9 | 10 | 11 | 11 | 11 | 9 | 7 | 5 | 3 |
| 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 |