Last updated: July 2, 2025
In Hiji, Japan, awareness of the UV Index is crucial for maintaining skin health and preventing sunburns. Understanding the varying UV levels throughout the day helps residents and visitors make informed decisions about sun protection. With a climate classified as Cfa (humid subtropical), Hiji experiences significant UV exposure, particularly during midday hours when the index peaks at 12. This highlights the importance of taking protective measures, such as wearing sunscreen and protective clothing, during the hours of highest UV activity. Stay informed to protect your skin and enjoy the vibrant outdoor life that Hiji has to offer!
The UV Index for the day reveals a dynamic shift in sun exposure, peaking dramatically between 11:00 AM and 1:00 PM. Starting the morning with a mild maximum of 2 at 7:00 AM, the index steadily rises, reaching 12 by midday—an indication of high risk for harm from unprotected sun exposure. As the afternoon progresses, it dips to 10 at 2:00 PM and then gradually decreases to a more moderate level of 4 by 4:00 PM. By the evening, the UV Index settles back down to 1 by 6:00 PM, signaling a safe time to enjoy the outdoors again. Be sure to protect your skin during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 11 | extreme | 10 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, the UV Index experiences significant fluctuations, with the highest risk months emerging from March to September. During this period, the UV Index peaks at 12, indicating an extreme exposure category from May to August, requiring only 10 minutes of sun exposure before risking skin damage. Conversely, January and December feature a moderate UV Index of 4, allowing for about 30 minutes of safe exposure. Visitors and residents are advised to take extra precautions during high-risk months, such as wearing sunscreen, protective clothing, and seeking shade during peak hours, particularly in the summer months when the potential for sunburn is acute. As the UV Index starts to decline in October and November, a return to more moderate sun safety measures becomes appropriate.
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 |
| Hiji | 4 | 6 | 9 | 11 | 12 | 11 | 12 | 12 | 11 | 7 | 6 | 4 |