Last updated: July 2, 2025
Understanding the UV Index in Rankoshimachi, Japan is crucial for safeguarding your skin health and preventing sunburn. With a climate characterized by Dfb conditions, residents and visitors can experience varying levels of UV exposure throughout the day. Notably, UV Index levels peak between 10 AM and 2 PM, reaching a maximum of 10, indicating a high risk of harm from unprotected sun exposure. By staying informed about the UV Index, you can take proactive measures to protect your skin and enjoy the outdoors safely in this beautiful region.
As the sun rises, the UV Index begins its ascent, peaking at 10 during the noon hour. Starting at a modest 2 at 07:00, the UV levels climb steadily, reaching 9 by 11:00 and holding strong at 10 by 12:00—a reminder to seek shade and apply sunscreen during this time. After noon, the index starts to taper off, dropping to 5 by 15:00, and sinking further to 1 by 17:00, where it remains until sunset. This data highlights the importance of being sun-smart, especially during the peak hours around midday when UV exposure is at its highest. Stay vigilant and protect your skin!
| 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 | 8 | very high | 15 min |
| 11:00 | 9 | 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 | 5 | moderate | 30 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so does the UV Index, indicating varying levels of sun exposure risk throughout the year. The high-risk months are primarily from May to September, where the UV Index peaks at 10, falling within the very high exposure category, necessitating a burn time of just 15 minutes. In contrast, January and December experience low UV levels with an index of 2, allowing for a safer burn time of 45 minutes. Residents and visitors should take extra precautions during the high-risk months by wearing sunscreen, protective clothing, and seeking shade during peak sun hours to minimize their risk of skin damage. In the cooler months, while the risk is lower, remaining vigilant is still advised to ensure overall skin health.
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 |
| Rankoshimachi | 2 | 3 | 6 | 7 | 9 | 10 | 10 | 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 |