Last updated: June 2, 2025
Understanding the UV Index in Niigata, Japan, is crucial for safeguarding your skin health and preventing sunburn. As a city that experiences a temperate Cfa climate, Niigata sees varying levels of UV radiation throughout the day, with the index peaking at an intense 11 around noon. This knowledge empowers residents and visitors alike to take necessary precautions during high UV times, ensuring safe outdoor experiences amidst the beauty of Niigata’s landscapes. With peak UV exposure typically occurring from 10 AM to 2 PM, knowing when to seek shade or apply sunscreen can make a significant difference in long-term skin health.
The UV Index exhibits a dynamic pattern throughout the day, peaking impressively at 12:00 PM with a striking value of 11, indicating a very high risk of harm from unprotected sun exposure. As early as 9:00 AM, the index jumps to 7, suggesting it’s time to start applying sunscreen. The intensity swells to 10 by 11:00 AM, urging sun safety measures. After reaching its zenith, the index gradually declines, dipping to 5 by 3:00 PM and eventually settling at a low of 0 by 7:00 PM. With these fluctuations, it’s crucial to be sun-smart, especially during peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 4 | 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 | 11 | extreme | 10 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 8 | very high | 15 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 | 0 | low | 45 min |
As the year progresses, the UV Index in our region exhibits significant fluctuations, reflecting seasonal changes that are essential for visitors and residents to note. During the winter months of January and February, the UV Index remains in the moderate range (3-4), allowing for a burn time of about 30 minutes. However, as spring approaches, particularly in March, the UV Index rises sharply to high (7), reducing burn time to 25 minutes. The months of April through August present the highest risk, with UV Index values reaching very high (8-9) in April and May, escalating to a peak of extreme (11) in July and August, where the burn time drops to just 10 minutes. By September, there’s a slight decline to very high (9), and it further reduces in the fall months, with the index returning to the moderate range by November and December. Residents and visitors should take care during high-risk months—particularly from March through September—by seeking shade, wearing protective clothing, and using sunscreen to safeguard against harmful UV exposure.
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 |
| Niigata | 3 | 4 | 7 | 8 | 9 | 10 | 11 | 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 |