Last updated: August 1, 2025
In Rusutsu, Japan, understanding the UV Index is crucial for maintaining skin health and avoiding sunburn. With its Dfb climate, characterized by warm summers and snowy winters, Rusutsu's weather can present varied UV exposure. On clear days, the UV index can peak as high as 10 around noon, indicating a moderate to high risk of harm from unprotected sun exposure. Awareness of these levels helps residents and visitors alike protect their skin and enjoy the beautiful outdoor activities this stunning resort offers throughout the year.
As the sun rises, the UV Index begins its ascent, starting at a modest 3 at 07:00. By 08:00, it ticks up to 4, signaling the day is gaining strength. A significant jump occurs by 09:00, reaching 7, and by 10:00, it hits an impressive 8, making sunscreen essential for outdoor enthusiasts. The sun reaches its zenith at 11:00 and 12:00, both peaking at a striking 10, marking the high point of the day for UV exposure. However, from 13:00 onwards, the index begins to decline, dropping to 9 at 13:00 and gradually falling to 5 by 15:00. A steady decrease continues until 17:00, when it drops to a safe 1, lingering at this low level until sunset at 19:00. Remember, taking precautions in the peak hours can help protect your skin from harmful rays!
| 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 | 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 | 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, the UV Index experiences significant fluctuations, reflecting shifts in seasonal sun exposure. January and December see low UV levels (Index 2), with burn times of 45 minutes, indicating minimal risk. As spring approaches, February (Index 3) and March (Index 6) signal moderate to high exposure risk, shortening burn times to 30 and 25 minutes respectively. The risk escalates dramatically in May through August, where UV Index values peak at 10, categorizing the exposure as very high, and reducing safe burn time to just 15 minutes. September remains high at 8, marking it as a continuation of the peak summer risk, after which the index drops to 6 in October and returns to moderate in November. For both residents and visitors, it is crucial to take precautions during the high-risk months of March to September, utilizing sunscreen, wearing protective clothing, and seeking shade, especially when the UV Index is significant.
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 |
| Rusutsu | 2 | 3 | 6 | 7 | 9 | 10 | 10 | 10 | 8 | 6 | 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 |