Last updated: August 1, 2025
Understanding the UV Index is crucial for residents of Akiruno, Japan, where sunlight can be both a blessing and a risk. The UV levels in this region typically spike to a maximum of 11 during the peak hours of 11:00 AM to 1:00 PM, indicating a very high potential for skin damage and sunburn within minutes of exposure. Being aware of these levels is essential not only for preventing painful sunburns but also for safeguarding long-term skin health. With Akiruno's Cfa climate providing warm summers and varying UV exposure risks, knowing when to seek shade, wear sunscreen, or don protective clothing can make all the difference in enjoying the outdoors safely.
As the sun rises, the UV Index begins its climb, starting at a modest 2 at 7:00 AM. By 8:00 AM, it gains momentum, reaching 4, but the real peak arrives between 10:00 AM and 12:00 PM, where it soars to a striking 11. This is the time to seek shade or wear protective gear, as the sun's rays are at their harshest. After noon, the intensity wanes slightly with readings of 10 at 1:00 PM and gently dropping to 8 by 2:00 PM. As the afternoon turns to evening, the index cools down to 5 at 3:00 PM, before dipping to 3 by 4:00 PM, and ultimately settling at 1 by 6:00 PM. By sunset, the danger fades, leaving a 0 UV reading at 7:00 PM. Keep an eye on the UV Index to enjoy the sun safely!
| 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 | 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 | 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 |
Throughout the year, seasonal changes in UV Index reveal significant variations in sun exposure risk. The high-risk months for UV exposure are predominantly from March to August, with the peak occurring in May, June, July, and August, where the UV Index reaches 11, categorized as extreme with a burn time of just 10 minutes. During this period, individuals are strongly advised to take precautions such as wearing sunscreen, protective clothing, and seeking shade, especially between 10 AM and 4 PM, when UV radiation is at its strongest. In contrast, the UV Index indicates moderate levels in January, November, and December, and high levels in October and February—months where sun safety should still be observed, though the urgency is somewhat reduced.
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 |
| Akiruno | 4 | 6 | 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 |