Last updated: May 3, 2025
Understanding the UV Index in Tosu, Japan is essential for protecting your skin and overall health in this vibrant city. With peak UV levels reaching as high as 11 during the midday hours, awareness of the UV Index can be a game-changer in preventing sunburn and long-term skin damage. Tosu's Cfa climate brings warm, humid summers, which amplify UV exposure risks. By keeping track of UV levels, you empower yourself to enjoy the sun safely, ensuring that outdoor activities remain pleasurable while safeguarding your skin's health.
At sunrise, the UV Index starts gently at 1 at 07:00, making it a safe time for morning activities. However, as the sun climbs higher, the intensity surges, reaching 3 by 08:00 and escalating to a peak of 11 between 12:00 and 13:00. This is the crucial window when protection from the sun is essential, as exposure can lead to skin damage. As afternoon progresses, the index gradually declines, settling back to 9 by 14:00. By the time evening approaches, the UV Index dips to 2 at 17:00 and returns to a minimal 1 by 18:00, signaling a return to safer levels. Whether you’re planning outdoor fun or just soaking up the sun, be mindful of these fluctuations for optimal UV safety!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 8 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | 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 | 1 | low | 45 min |
Throughout the year, seasonal changes in UV exposure highlight periods of heightened risk for residents and visitors. From January to February, the UV Index rises from 4 (moderate) to 6 (high), reducing safe exposure time to 25 minutes. Significant increases occur in March, reaching 8 (very high), and peaking during the summer months of April to August at 11-12 (extreme), where only 10 minutes of unprotected exposure is advisable. The risk, while still present, decreases again in September and returns to high levels in October and November with a UV Index of 6-7, allowing for 25 minutes of safe exposure. As such, it is crucial for visitors and residents to remain vigilant, especially during the summer, taking precautions like wearing sunscreen, protective clothing, and seeking shade during peak hours to mitigate the risk of UV-related health issues.
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 |
| Tosu | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 12 | 11 | 7 | 6 | 4 |