Last updated: May 3, 2025
Understanding the UV Index is crucial in Niki, Japan, where outdoor enthusiasts and residents alike are exposed to varying levels of ultraviolet radiation throughout the year. With a climate categorized as Dfb, Niki experiences significant UV exposure, particularly during midday hours when levels peak at 9. Being aware of these levels is essential for preventing sunburn and maintaining long-term skin health. By knowing when to seek shade or apply sunscreen, you can enjoy the beautiful outdoors while protecting your skin from potential damage. Stay informed, stay safe, and embrace the sun responsibly in Niki!
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 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 |