Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors of Semboku, Japan, where the climate often exposes individuals to varying levels of ultraviolet radiation. With peak UV levels reaching 9 around midday, awareness is essential for preventing sunburn and promoting overall skin health. Given Semboku’s Dfb climate, characterized by warm summers, residents should be particularly mindful of the heightened UV risks during sunny days. Being informed about UV levels can empower you to take protective measures, ensuring you enjoy the outdoors safely.
As the sun rises, the UV Index begins its ascent, peaking at 11:00 AM and 12:00 PM with a blistering 9. The day starts gently, with 07:00 AM registering a modest 2, but by 09:00 AM, it climbs to a moderate 6. The intensity escalates, hitting 8 at 10:00 AM and reaching its zenith shortly after noon. After this peak, the index gradually dips, easing down to 6 by 2:00 PM, before falling further to 4 at 3:00 PM. As evening approaches, the UV radiation wanes significantly, dropping to 2 by 4:00 PM and near zero after sunset, signaling a shift in the skies. Remember to protect your skin during those peak hours!
| 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 | 9 | very high | 15 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 4 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, the UV Index experiences notable fluctuations, with high-risk months occurring between April and August. In April and May, the UV index peaks at 9, categorized as very high, requiring quick precautions with just 15 minutes of burn time. June and July sustain a UV Index of 10, also indicating very high levels, while August reaches an extreme UV Index of 11, minimizing safe sun exposure to just 10 minutes. In contrast, the UV levels are moderate from January to February and again from October to December, notably lowering burn times back to 30 minutes. Visitors and residents are strongly advised to protect their skin with sunscreen, hats, and protective clothing especially during the highest UV Index periods, ensuring they avoid prolonged sun exposure during peak hours. Stay informed and prioritize skin safety!
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 |
| Semboku | 3 | 4 | 6 | 9 | 9 | 10 | 10 | 11 | 9 | 6 | 4 | 3 |
| 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 |