Last updated: July 2, 2025
Understanding the UV Index in Rumoi, Japan is crucial for protecting your skin health under its varying sun exposure. With maximum UV levels peaking at 9 between 11:00 AM and 1:00 PM, awareness of these readings can be vital in preventing sunburn and long-term skin damage. Rumoi's Dfb climate means that while summers can bring strong UV rays, winter can also expose you to harmful levels of UV radiation, particularly when reflected off snow. By staying informed about the UV Index, you can enjoy the beautiful outdoor moments in Rumoi while keeping your skin safe!
The day begins gently with a UV Index of 3 at 07:00, making it a safe start for morning activities. As the sun rises higher, the intensity increases; by 10:00, it reaches 8, peaking at 11:00 and 12:00 with a high of 9. This signals a perfect time for sun protection as midday approaches. The UV Index begins to decline in the afternoon, dropping to 4 at 15:00, and further cooling off to 1 by 17:00, creating a more forgiving environment as the sun sets. Plan your sunshine hours wisely, as the peak between 10:00 and 12:00 offers the highest risk for unprotected skin!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 3 | moderate | 30 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 | 7 | high | 25 min |
| 15:00 | 4 | 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 fluctuates, indicating varying levels of sun exposure risk. January and December present the lowest UV levels (2), categorized as low, allowing for longer exposure times of 45 minutes without burning. As spring approaches, February and March see a moderate rise in UV Index (3 to 5), with a reduced burn time of 30 minutes. April marks a significant shift to a high exposure category (UV Index 7), followed by the very high category from May to September, peaking at an index of 9 during the summer months, where the burn time reduces sharply to just 15 minutes. October and November see a decline back to a moderate level (UV 5 and 3, respectively). Visitors and residents should be particularly cautious during the high-risk months of May through September, applying sunscreen regularly and seeking shade to minimize the risk of sunburn during these times of intense UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rumoi | 2 | 3 | 5 | 7 | 8 | 9 | 9 | 9 | 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 |