Last updated: August 1, 2025
Understanding the UV Index is essential for residents and visitors in Ozu, Japan, where sunny days can pose significant risks to skin health. With peak UV levels soaring to 12 around midday, the potential for sunburn and long-term skin damage escalates without proper precautions. This insight is particularly critical in Ozu’s humid subtropical climate (Cfa), which intensifies UV exposure during warm months. By being aware of these levels, you can take proactive steps to protect yourself and enjoy the beautiful outdoors safely. Prioritizing UV awareness not only helps prevent immediate harm but also supports your long-term skin health in this vibrant region.
The UV Index throughout the day showcases a dynamic shift in sun intensity, peaking at 12 around noon. Beginning with a gentle 2 at 7:00 AM, the index steadily increases, hitting 11 by 11:00 AM as the sun climbs higher. By 12:00 PM, the sun reaches its zenith at 12, marking the highest UV exposure, making sun safety a priority. As the afternoon progresses, from 1:00 PM to 3:00 PM, the UV Index gradually decreases to 9 by 2:00 PM and 7 by 3:00 PM. The day winds down with a notable drop in intensity, returning to a mild 1 by 6:00 PM, emphasizing that the safest time to enjoy the sun is before noon or after 4:00 PM.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 8 | very high | 15 min |
| 11:00 | 11 | extreme | 10 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV radiation levels dramatically fluctuate, impacting the risk of skin damage for both visitors and residents. The highest risk months occur from May to August, where the UV Index peaks at 11 to 12, indicating an extreme exposure category with a burn time of just 10 minutes. During these months, it is crucial to limit direct sun exposure and utilize protective measures such as sunscreen, hats, and clothing to safeguard skin health. March and April also present high levels of concern, categorized as very high with burn times of just 15 minutes. As seasons shift into fall and winter, the UV Index decreases, with December and January showing a moderate level, allowing for longer safe exposure times of 30 minutes. However, even during lower UV months, protective precautions are still advised. Stay informed and protect yourself year-round!
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 |
| Ozu | 4 | 6 | 8 | 10 | 11 | 11 | 12 | 12 | 10 | 7 | 6 | 4 |