Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Chuo, Japan, where the combination of a Dfb climate and high sunlight exposure can lead to increased UV radiation levels, particularly around midday. Being aware of the UV Index helps in making informed decisions about sun protection to prevent sunburn and long-term skin damage. During peak hours, such as from 10 AM to 2 PM, the UV Index can reach levels as high as 12, indicating a very high risk of harm from unprotected sun exposure. By staying informed about UV levels, you can better safeguard your skin while enjoying the vibrant outdoor life that Chuo has to offer.
The UV Index today starts off relatively mild, peaking at 3 by 07:00. As the sun rises higher, the intensity escalates to 5 at 08:00, reaching a significant 8 by 09:00. The intensity continues to climb and hits a maximum of 12 at 12:00, prompting caution for outdoor activities. 11 at 11:00 and 10 at 13:00 keep the UV levels high, before they start to taper off. By 15:00, it drops to 6, then quickly declines to 3 by 16:00. The sun's retreat is apparent as the index falls to 2 at 17:00 and ultimately settles at a low 0 by 19:00, making the evening hours safe for all. Stay sun-smart and protect your skin during peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 3 | moderate | 30 min |
| 08:00 | 5 | moderate | 30 min |
| 09:00 | 8 | very high | 15 min |
| 10:00 | 10 | very high | 15 min |
| 11:00 | 11 | extreme | 10 min |
| 12:00 | 12 | 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, the UV Index demonstrates significant seasonal variations, highlighting the importance of sun protection during peak months. From March to August, the UV Index reaches its highest levels, peaking at 12 in June, July, and August, which falls under the extreme exposure category with a burn time of just 10 minutes. This indicates that March through August are the high-risk months for UV exposure, particularly April and May, which see indices of 10 and 11 respectively. Residents and visitors are advised to take extra precautions during these months, including wearing sunscreen, protective clothing, and seeking shade, especially during the midday hours. As the year progresses into the autumn and winter months, UV levels decrease, but awareness should still be maintained in February, October, and November, where the UV Index remains in the high range.
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 |
| Chuo | 4 | 7 | 9 | 10 | 11 | 12 | 12 | 12 | 10 | 7 | 6 | 4 |