Last updated: June 2, 2025
Staying informed about the UV Index is crucial for residents of Yurihonjo, Japan, where the climate often presents significant sun exposure risks. Understanding the daily UV levels is not just about preventing sunburn; it's essential for maintaining long-term skin health and reducing the risk of skin damage. With peak UV Index values hitting 10 between 11:00 AM and 12:00 PM, Yurihonjo's Cfa climate can lead to hazardous conditions if precautions aren’t taken. Being aware of these risks allows you to enjoy the outdoors while protecting your skin from harmful ultraviolet rays.
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 |
Throughout the year, the UV Index exhibits notable seasonal fluctuations, with higher values indicating greater risk of skin damage from sun exposure. March marks the beginning of high UV exposure with an index rising to 6, designating it as a high-risk month. This trend peaks in August with an extreme UV Index of 11, highlighting the highest risk period for sunburn. April to September remains critical, with indices frequently at or above 8, suggesting burn times as short as 10 minutes in the peak months of June and July. To protect against harmful UV radiation, visitors and residents should prioritize sun safety during these months by seeking shade, wearing protective clothing, and applying broad-spectrum sunscreen. Conversely, during December, the UV Index drops to a low level of 2, offering a safer environment for outdoor activities without intense sun protection needs. Always stay vigilant about UV levels, especially when planning outdoor activities between March and September.
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 |
| Yurihonjo | 3 | 3 | 6 | 8 | 9 | 10 | 10 | 11 | 9 | 6 | 4 | 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 |