Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in Kasagi, Japan, where the subtropical climate can lead to varying levels of sun exposure throughout the year. The UV Index not only helps in preventing sunburn but also plays a significant role in maintaining long-term skin health. With peak UV levels reaching 11 during midday hours, it's essential to be aware of these red flags for skin protection. Kasagi's climate, classified as Cfa, brings both warmth and sun, highlighting the importance of staying informed about daily UV risks to safeguard against harmful effects of overexposure.
As the sun rises, the UV Index begins its ascent, starting at a gentle 2 at 07:00. By 08:00, it climbs to 4, indicating that protective measures are beginning to be advisable. The intensity peaks at 11 during the 11:00 and 12:00 hours, marking the time when sunlight is most potent. As the afternoon progresses, the index starts to decline; by 14:00, it drops to 8, and further diminishes to 6 by 15:00. As evening approaches, the UV Index wanes significantly, reducing to 3 at 16:00 and sinking to a mild 1 by 18:00, indicating a much lower risk. Overall, it’s a sun-soaked day, urging outdoor enthusiasts to be mindful of sun exposure, especially during those peak hours!
| 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 | 8 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest levels observed from March to August, peaking at a UV Index of 12 in July. This period includes extreme levels of risk, where the recommended burn time is as little as 10 minutes. Visitors and residents should exercise caution during these months, particularly in April, May, June, and July, by seeking shade, wearing protective clothing, and using sunscreen. Conversely, January, November, and December present lower risk categories, with moderate exposure and longer burn times of 30 minutes. To ensure safety, it’s crucial to stay informed about the UV Index and adjust outdoor activities accordingly throughout the year.
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 |
| Kasagi | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |