Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Nanao, Japan, where the subtropical Cfa climate often leads to elevated sun exposure throughout the year. With UV levels peaking at 10 around noon, it’s essential to grasp how these readings impact sunburn prevention and long-term skin health. By staying informed about the daily UV Index, you can effectively protect yourself from harmful effects, ensuring your outdoor activities remain enjoyable and safe amidst Nanao's stunning landscapes. Don't let the sun catch you off guard—understand your UV risks and bask in the beauty of Nanao responsibly!
The UV Index throughout the day showcases a significant rise in solar intensity, peaking at 12:00 PM with a robust level of 10. Early risers will experience moderate exposure, with values starting at 2 by 7:00 AM and gradually climbing. By 10:00 AM, the UV Index reaches 8, prompting a recommendation for protective measures. The afternoon sees it peak again at 11:00 AM with a 9 before tapering off in the subsequent hours. As the sun starts to descend, the UV levels decline noticeably, dropping to 0 by 7:00 PM. It's essential to stay mindful of these fluctuations, especially during midday when the sun is at its strongest.
| 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 | 8 | very high | 15 min |
| 11:00 | 9 | 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 |
The UV Index experiences significant seasonal changes, with high-risk months occurring from March to September. During this period, the UV Index escalates from moderate levels of 3 in January and February to extreme levels of 11 in June, July, and August. The burn time dramatically decreases, from 30 minutes in January and February to just 10 minutes in the peak summer months. Visitors and residents are strongly advised to take proper precautions during the high-risk months by applying sunscreen, wearing protective clothing, and limiting sun exposure, especially between 10 AM and 4 PM when UV radiation is at its peak. After September, the UV Index begins to decline, but vigilance is still recommended through October.
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 |
| Nanao | 3 | 4 | 7 | 10 | 10 | 11 | 11 | 11 | 9 | 7 | 5 | 3 |
| 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 |