Last updated: May 3, 2025
Understanding the UV Index is essential for residents and visitors in Kasagi, Japan, where the climate can be characterized as Cfa—humid subtropical, with hot summers and mild winters. Being aware of the UV levels throughout the day is crucial for sunburn prevention and long-term skin health. In Kasagi, the UV index peaks at a significant 11 around midday, posing a considerable risk for skin damage if proper precautions are not taken. By staying informed about the daily UV exposure, you can protect yourself and enjoy the beautiful outdoors safely.
The UV Index for the day follows a dynamic trend, peaking during the midday hours. Starting at a modest 2 at 7:00 AM, the intensity gradually intensifies, reaching 4 by 8:00 AM. As the sun climbs higher, the index escalates significantly, hitting a striking 9 at 10:00 AM and reaching its zenith of 11 at 12:00 PM. After this peak, a gradual decline sets in, with the index dropping to 5 by 3:00 PM before tapering off to 1 by 5:00 PM. The day concludes with a UV Index of 0 by 7:00 PM, signaling a clear drop in potential UV exposure. It's a reminder to stay sun-smart, especially during the midday hours when the UV rays are at their strongest!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 4 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 5 | moderate | 30 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest levels observed from March to August, peaking at a UV Index of 12 in July. This period includes extreme levels of risk, where the recommended burn time is as little as 10 minutes. Visitors and residents should exercise caution during these months, particularly in April, May, June, and July, by seeking shade, wearing protective clothing, and using sunscreen. Conversely, January, November, and December present lower risk categories, with moderate exposure and longer burn times of 30 minutes. To ensure safety, it’s crucial to stay informed about the UV Index and adjust outdoor activities accordingly throughout the year.
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 |
| Kasagi | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |