Last updated: July 2, 2025
In Shiraoi, Japan, being aware of the UV Index is crucial for safeguarding your skin against the harmful effects of ultraviolet radiation. Understanding UV levels is essential not only for preventing sunburns but also for maintaining long-term skin health. With a Dfb climate, Shiraoi experiences a range of UV exposure, peaking at a high of 10 around noon. This highlights the importance of taking appropriate precautions to enjoy the outdoors safely, whether you’re soaking up the sun or engaging in outdoor activities during those high-risk hours. Stay informed, stay protected!
As the sun rises, the UV Index begins to climb steadily, starting at a mild 3 by 07:00. By 09:00, it hits a noticeable 7, urging early risers to take precautions. The peak occurs at 12:00, reaching a striking 10, marking the day's most intense exposure. As the afternoon progresses, the index gradually declines, dipping to 7 by 14:00 and then further to 5 at 15:00. By 16:00, it begins its descent, dropping to a gentle 3 and finally stabilizing at a low 1 by 17:00 onwards. It's a reminder that while midday sun can be powerful, the evening brings solace with its reduced UV levels. Stay protected when UV rays are at their highest, especially during mid-day!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 3 | moderate | 30 min |
| 08:00 | 4 | moderate | 30 min |
| 09:00 | 7 | 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 |
Throughout the year, the UV Index demonstrates significant seasonal variations that highlight the importance of sun safety. From January to March, the UV levels are generally low to moderate, with burn times ranging from 30 to 45 minutes. However, April marks the start of high-risk months, peaking with May and August, where the UV Index reaches a very high level of 9 and 10, drastically reducing safe sun exposure to just 15 minutes. Following these months, September and October maintain elevated UV levels before returning to more moderate levels in November and December. Residents and visitors are strongly advised to take precautions during high-risk months (April through September) by wearing sunscreen, protective clothing, and seeking shade during peak sun hours to minimize the risk of skin damage.
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 |
| Shiraoi | 2 | 3 | 5 | 7 | 9 | 10 | 9 | 10 | 8 | 6 | 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 |