Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in Kashiba, Japan, where the climate often leads to significant sun exposure. With UV levels peaking at dangerous highs—reaching an 11 during midday—it’s essential to grasp how these levels can impact your skin health and lead to sunburn. Kashiba’s humid subtropical climate (Cfa) not only brings hot summers but also poses unique risks, making it vital to stay informed about daily UV levels to protect yourself and enjoy the outdoors safely. Knowing when to seek shade or apply sunscreen can make all the difference in safeguarding your skin!
As the sun rises, the UV Index begins at a mild 2 by 07:00. It steadily escalates, reaching 4 at 08:00, and then surges to a peak of 11 between 11:00 and 12:00—this is when the sun is most intense. Vigilance is essential during these hours, as the risk of skin damage increases significantly. As the afternoon progresses, the UV levels gradually decline; 10 at 13:00, followed by a decrease to 8 at 14:00, a more manageable 6 at 15:00, and finally tapering off to 3 by 16:00. By 17:00, the index drops to 2, and the evening settles in with a minimal 1 by 18:00 and 19:00. It's a day of high UV exposure, urging outdoor enthusiasts to take precautions during peak hours.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 4 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 11 | extreme | 10 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest risk occurring during the late spring and summer months. From April to August, the UV Index peaks at 11 to 12, representing an extreme exposure category, with a rapid burn time of just 10 minutes. Notably, March and September are also high-risk months, with UV Index levels of 8 and 10, respectively. To protect against harmful UV radiation, it is essential for both visitors and residents to take precautions during these peak months: seek shade, wear protective clothing, and apply broad-spectrum sunscreen regularly, especially between 10 AM and 4 PM. In contrast, during the winter months (January, December), UV levels drop to moderate, offering lower risk for skin damage, with longer burn times of 30 minutes.
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 |
| Kashiba | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 12 | 10 | 7 | 6 | 4 |