Last updated: July 2, 2025
Understanding the UV Index in Niki, Japan is essential for everyone who enjoys outdoor activities in this beautiful region. With UV levels peaking at 9 during midday, knowing when and how to protect your skin from harmful radiation can significantly reduce the risk of sunburn and long-term skin health issues. Niki's Dfb climate—characterized by warm summers and cold winters—means varying UV exposure throughout the year, but it’s crucial to remain vigilant during the sunniest months. Stay informed and keep your skin safe by tracking the UV Index and practicing sun safety!
The UV Index steadily climbs throughout the morning, peaking at 9 between 11:00 and 12:00, indicating intense sun exposure that requires caution. As the day progresses, the index begins to decline, dropping to 7 by 14:00 and further decreasing to 5 by 15:00. By late afternoon, the UV levels drop significantly, reaching 1 by 16:00 and remaining low until sunset. It's crucial to stay protected during the midday hours when the UV Index is at its highest; wearing sunscreen and protective clothing is highly recommended to enjoy safe outdoor activities!
| 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 | 9 | very high | 15 min |
| 13:00 | 8 | 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 reflects significant seasonal changes that impact exposure risks. January and December have low UV levels (Index 2), where burn times extend to 45 minutes. As spring approaches, by March the Index rises to 5, indicating moderate exposure risk. However, from April to September, the UV Index reaches high to very high levels, peaking at 10 in August, with burn times decreasing sharply to just 15 minutes. These months—April through September—pose the highest risk for sunburn, particularly May through August when the levels are consistently very high. Visitors and residents should prioritize sun protection during these months, recommending the use of sunscreen, hats, and protective clothing, and to seek shade during peak hours to minimize UV exposure. By October and November, the UV levels drop to moderate again, allowing for safer outdoor activities.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Niki | 2 | 3 | 5 | 7 | 9 | 9 | 9 | 10 | 8 | 5 | 3 | 2 |
| 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 |