Last updated: July 2, 2025
In Motosu, Japan, understanding the UV Index is crucial for maintaining skin health and preventing sunburn, especially during the warm months. With a Cfa climate, residents and visitors alike are often exposed to varying UV levels that can reach a peak of 11 by midday, indicating a very high risk of harm from unprotected sun exposure. By being aware of the daily UV levels, you can take proactive measures to protect your skin and enjoy outdoor activities safely. Whether it’s the vibrant summer sun or reflective light from surrounding lakes, staying informed about UV risks can make all the difference in safeguarding your health.
As the sun rises, the UV Index begins its ascent, starting at a mild 2 at 07:00. By 08:00, it climbs to 4, hinting at a brighter day ahead. The intensity peaks around 11:00 and 12:00, where it reaches an impressive 11, calling for caution as rays intensify. Midday to early afternoon (12:00 - 14:00) is the most formidable, with the index hovering around 10 and 8 before gradually descending. By 17:00, it dips back to a manageable 2, and as evening sets in, the sun's grip fades, dropping to 0 by 19:00. This dynamic pattern highlights the necessity of sun protection, especially during the 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 | 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 | 6 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV exposure varies significantly, peaking during the summer months. High-risk months for UV exposure are from March to August, when the UV Index reaches its maximum levels of 10 to 11 and the burn time is as brief as 10 minutes. Notably, May through August features extreme exposure, requiring diligent sun protection practices. As the year transitions into fall, September to November sees a decrease in UV levels, with October still posing a moderate risk. To ensure safety, visitors and residents are advised to wear protective clothing, use sunscreen, and seek shade during the peak sun hours, especially from late spring through summer when the threat of sunburn is greatest.
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 |
| Nagoya UVI | 4 | 6 | 8 | 10 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 3 |
| Motosu | 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 |