Last updated: August 1, 2025
In Namioka, Japan, staying informed about the UV Index is crucial for protecting your skin and overall health. With peak UV levels reaching up to 10 around midday, understanding these fluctuations can help you prevent sunburn and reduce long-term skin damage. Given Namioka’s Cfa climate, characterized by warm summers and high humidity, residents and visitors alike must be vigilant about UV exposure risks throughout the day. Being aware of the UV Index empowers you to enjoy the sun safely while safeguarding your skin against harmful rays.
During the early morning hours, the UV Index starts off mild, peaking at 3 by 7:00 AM. As the sun climbs higher, the intensity increases, hitting 4 by 8:00 AM and dramatically soaring to a peak of 10 at both 11:00 AM and 12:00 PM. This high level indicates a very high risk for harm from unprotected sun exposure. The afternoon brings a gradual decline, with the index dropping to 9 at 1:00 PM before easing down to 5 by 3:00 PM. As the sun sets, the UV Index gently recedes to 1 by 5:00 PM, ultimately falling to 0 by 7:00 PM, signaling a safe end to UV exposure for the day. Stay protected when the index is high, and enjoy the sun responsibly!
| 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 | 11 | extreme | 10 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 |
Throughout the year, UV levels fluctuate significantly, with higher levels observed from March to September. The peak risk months are June, July, and August, where the UV Index reaches as high as 11, categorized as extreme, boasting a burn time of just 10 minutes. In spring, particularly April and May, the UV exposure escalates to very high levels (Index of 8-9), requiring heightened awareness. From October to March, UV Index values decrease, though residents and visitors should still take precautions in March (Index of 6) and October (Index of 6) due to higher risk levels. As a general guideline, it’s advisable to wear sunscreen and protective clothing, especially during peak hours, from March to August, to minimize sun exposure and reduce the risk of 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 |
| Namioka | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 11 | 8 | 6 | 4 | 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 |