Last updated: May 3, 2025
In Nikko, Japan, staying informed about the UV Index is crucial for protecting your skin from harmful ultraviolet rays. With a climate classified as Cfa, which brings warm summers and moderate to cool winters, the UV levels can peak dramatically, particularly around midday. Understanding these levels is essential not only for sunburn prevention but also for long-term skin health. During the summer months, UV exposure can reach a maximum of 10 around noon, underscoring the importance of taking precautions, such as seeking shade and applying sunscreen, to minimize risks and enjoy all that Nikko has to offer safely.
The UV Index starts the day at a moderate level of 3 at 07:00, gradually climbing to a peak of 10 between 11:00 and 12:00, indicating the highest risk of harm from unprotected sun exposure. As the day progresses, intensity wanes, dipping to 7 by 14:00 and further to 5 by 15:00. By late afternoon, the index drops significantly, reaching 2 at 16:00 and cooling off to 1 by 17:00 and beyond. Sun safety is paramount, especially during midday hours, so remember to seek shade and wear protection when the sun is at its strongest!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 3 | moderate | 30 min |
| 08:00 | 5 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 10 | 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 | 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, UV Index levels fluctuate significantly, with the highest risk months occurring from March to August. During this peak season, the UV Index reaches an extreme level of 11, indicating a burn time of only 10 minutes, highlighting the need for vigilant sun protection. February also presents a noticeable increase, with a high index of 6, while January begins with a moderate index of 4. As the year progresses, the UV levels gradually decrease, with November and December being the safest months to enjoy outdoor activities, featuring moderate indices of 5 and 3, respectively. Visitors and residents are strongly advised to take precautions during the high-risk months by applying sunscreen regularly, wearing protective clothing, and seeking shade during peak sunlight hours to minimize the risk of UV exposure and 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 |
| 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 |
| Nikko | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 11 | 10 | 7 | 5 | 3 |
| 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 |