Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors of Himimachi, Japan, where the climate offers warm summers and mild winters, creating a perfect backdrop for outdoor activities. As UV levels can reach a peak of 10 around midday, being aware of these values is essential to prevent sunburn and protect skin health. Regularly monitoring the UV Index helps you take informed precautions, ensuring that you enjoy the beautiful sunny days in Himimachi without compromising your well-being. Remember, even when the temperature feels mild, those UV rays can be deceptively strong!
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 |
As the seasons change, so do UV levels, with significant increases during the warmer months. From March to August, the UV Index rises dramatically, peaking at 11 (extreme) in June, July, and August, where burn times are as short as 10 minutes. April and May also present high risk, with a UV Index of 10 (very high) and burn times of 15 minutes. Conversely, the risk decreases significantly in the cooler months, with a moderate exposure category during January, February, November, and December, allowing for 30 minutes of safe sun exposure. Visitors and residents should take extra precautions from March to September, using sunscreen, wearing protective clothing, and seeking shade, especially during peak hours, to minimize sun damage.
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 |
| Himimachi | 3 | 5 | 7 | 10 | 10 | 11 | 11 | 11 | 9 | 6 | 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 |