Last updated: August 1, 2025
Understanding the UV Index in Chichibu, Japan, is essential for protecting your skin and overall health. With weather typically characterized by a Cfa climate, Chichibu experiences significant UV exposure, especially during peak hours when the index can soar to 12—a level that can lead to serious sunburn in just minutes. By being aware of UV levels, residents and visitors alike can take necessary precautions to mitigate risks, ensuring their outdoor activities remain enjoyable and safe. Stay informed and keep your skin healthy by checking the UV Index regularly!
As the day begins, UV Index levels start low at 2 by 7:00 AM, making for a gentle morning. However, the sun rises higher, and by 10:00 AM, the intensity peaks at a powerful 10, reaching a maximum of 12 by 12:00 PM. This intense UV exposure is most pronounced at 11:00 AM, where it reaches 11. As the afternoon unfolds, the UV Index gradually declines; it slips to 8 by 2:00 PM and continues to drop, tapering to 6 at 3:00 PM before settling down to a mild 1 by 5:00 PM. By evening, the UV risk diminishes further, reaching 0 by 7:00 PM, signaling a safe end to the day's sun. Ideal for planning outdoor activities, this data underscores the importance of sun protection 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 | 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, the UV Index demonstrates notable seasonal changes, with the most intense exposure occurring from April to August. During these months, the UV Index reaches extreme levels (10-12), significantly reducing the burn time to just 10 minutes. March and September also pose risks with very high levels (8-10), allowing for a burn time of only 15 minutes. Consequently, February and October present high levels (6-7), where protective measures are still advised with adjusted burn times of 25 minutes. Residents and visitors should exercise caution and protect their skin, especially during the high-risk months of April through August, by using sunscreen, wearing protective clothing, and limiting sun exposure during peak hours.
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 |
| Osaka UVI | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |
| Chichibu | 4 | 6 | 8 | 10 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 4 |