Last updated: July 2, 2025
In Hannan, Japan, being aware of the UV Index is crucial for protecting your skin and maintaining overall health. Understanding UV levels can help you prevent sunburn and reduce the risk of long-term skin issues, especially during the peak hours when UV rays are most intense. With a Cfa climate, Hannan experiences varying UV exposure, particularly from 10 AM to 1 PM when the index reaches its maximum of 11. By staying informed about the daily UV Index, you can enjoy the sunny days with confidence, ensuring that you take the right precautions for your skin health.
The UV Index data paints a clear picture of a sun-soaked day, starting with a gentle maximum of 2 at 7:00 AM. As the sun rises higher, the intensity builds, peaking at an impressive 11 around 11:00 AM to 1:00 PM. This period of extreme UV exposure underscores the importance of sun safety, urging everyone to seek shade or apply sunscreen. As afternoon sets in, the index gradually declines, dropping to 8 at 2:00 PM, followed by a gentle slide to 6 at 3:00 PM, before winding down to a calmer 1 by 6:00 PM. Overall, it’s a day to enjoy the sunshine while being mindful of its powerful rays!
| 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 | 11 | extreme | 10 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 |
The UV Index varies throughout the year, reflecting significant seasonal changes in sun exposure. From January to February, the UV Index remains moderate, with a burn time of 30 minutes. As spring arrives in March, the index escalates to 8, categorizing it as very high, with a reduced burn time of 15 minutes. The months of April through August peak at an extreme UV Index of 11, with burn times dropping to just 10 minutes, making this period particularly high-risk for sunburn. September sees a slight decline to a 10, categorized as very high, while October (UV Index of 7) shifts to high risk, allowing for 25 minutes of burn time. The year concludes with moderate exposure levels in November and December (UV Index 5 and 4, respectively), where burn times revert to 30 minutes. Visitors and residents should take precautions during high-risk months—especially from March to September—by using sunscreen, wearing protective clothing, and seeking shade to minimize UV exposure.
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 |
| Hannan | 4 | 5 | 8 | 11 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 4 |
| Osaka UVI | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |