Last updated: August 1, 2025
In Kobayashi, Japan, staying informed about the UV Index is essential for safeguarding your skin and overall health. Understanding UV levels is crucial for preventing sunburn and long-term skin damage, especially during the peak UV hours when levels can soar. Kobayashi's humid subtropical climate, characterized by warm summers, elevates the risk of UV exposure, particularly between 10 AM and 2 PM when the index reaches its highest, often hitting 12. By monitoring the UV Index, you can take proactive steps to protect yourself and enjoy the vibrant outdoor lifestyle that this beautiful region has to offer.
The UV Index for the day reveals a dynamic shift in sun exposure, peaking dramatically between 11:00 AM and 1:00 PM. Starting the morning with a mild maximum of 2 at 7:00 AM, the index steadily rises, reaching 12 by midday—an indication of high risk for harm from unprotected sun exposure. As the afternoon progresses, it dips to 10 at 2:00 PM and then gradually decreases to a more moderate level of 4 by 4:00 PM. By the evening, the UV Index settles back down to 1 by 6:00 PM, signaling a safe time to enjoy the outdoors again. Be sure to protect your skin during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 8 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | 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, UV index levels show significant variation, with the highest risk months being May through September, where the index reaches an extreme level of 12 and a burn time as short as 10 minutes. Notably, March and April also pose high risks with a very high index of 10. In contrast, the UV index drops to moderate levels in January (5) and December (4), allowing for safer sun exposure. Visitors and residents are advised to remain vigilant during the high and extreme UV months, applying broad-spectrum sunscreen, wearing protective clothing, and seeking shade, particularly between 10 AM and 4 PM when UV radiation is strongest.
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 |
| Kobayashi | 5 | 6 | 10 | 10 | 12 | 12 | 12 | 12 | 11 | 8 | 6 | 4 |