Last updated: June 2, 2025
Staying informed about the UV Index is crucial for residents and visitors in Daisen, Japan, where the sunny climate can lead to significant sun exposure. Understanding the varying UV levels throughout the day helps prevent sunburn and protects skin health, making it essential for enjoying outdoor activities safely. Daisen's Cfa climate presents unique risks, particularly during peak UV times when indices reach as high as 10 around midday. By keeping an eye on the UV Index, you can safeguard your skin while enjoying all that this beautiful region has to offer.
During the day, the UV Index experiences a dynamic shift, peaking in the late morning. Starting at 3 at 07:00, it escalates to reach a high of 10 by 11:00 and remains there until 12:00. As afternoon approaches, the index gradually declines, dropping back to 9 by 13:00, then to 7 at 14:00. By the mid to late afternoon, it continues its descent, falling to 5 at 15:00 and further down to 3 by 16:00. In the evening, the index diminishes significantly, plummeting to 1 at both 17:00 and 18:00, and finally reaching 0 by 19:00. This pattern highlights the importance of sun protection during the peak hours of 10:00 to 12:00 when the UV radiation is most intense.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 3 | moderate | 30 min |
| 08:00 | 5 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 10 | 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 the UV levels, with significant peaks occurring during the summer months. From March to August, the UV Index escalates from a moderate level of 6 in March to an extreme level of 11 in August, indicating a heightened risk for skin damage. April through September represents the high-risk months where the UV Index is categorized as very high to extreme, with burn times decreasing to as little as 10 minutes in August. To safeguard against harmful UV exposure, it is crucial for both visitors and residents to practice sun safety during these months by seeking shade, wearing protective clothing, and applying sunscreen regularly, even on cloudy days. In contrast, the UV Index drops back to a moderate level of 4 in February and 3 during January and December, suggesting lower risk during these winter months.
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 |
| Daisen | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 11 | 9 | 6 | 4 | 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 |