Last updated: May 3, 2025
Understanding the UV Index in Onagawa Cho, Japan, is essential for safeguarding your skin health and preventing sunburn. Given its Cfa climate, residents and visitors experience varying UV levels throughout the day, with peak exposure reaching a significant 10 around midday. This makes awareness of daily UV levels crucial, as even moderate sun exposure can lead to long-term skin damage. By keeping track of the UV Index, you can better protect yourself from the sun's harmful effects while enjoying the beautiful outdoors in Onagawa Cho.
The UV Index climbs steadily throughout the morning, peaking at a maximum of 10 at 11:00 AM. Early risers will notice a moderate 3 at 07:00, but by 08:00, it escalates to a higher 5. The sun takes center stage by 09:00, reaching 7, and by the time it's 10:00, it soars to a 9. As the clock strikes 11:00 AM, sun worshippers should take heed as the index hits its highest point. After lunchtime, the UV Index begins to descend gracefully, dropping to 8 at 1:00 PM and further declining to 6 at 2:00 PM. By late afternoon, it falls to 4 at 3:00 PM, quickly diminishing to a mere 1 by 5:00 PM, before concluding with a safe 0 at 7:00 PM. Always remember to protect your skin during those peak hours!
| 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 | 9 | very high | 15 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 4 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV Index values exhibit significant seasonal changes, with peak exposure occurring during the summer months. High-risk months include April through August, with the highest levels recorded in August (UV Index 11, extreme exposure), where the burn time reduces to just 10 minutes. From March onwards, the UV Index rises steadily, reaching very high levels in April (UV Index 8) and remaining at this level through September. January through February present moderate UV indices (3-4), offering a safer period for outdoor activities with longer burn times of 30 minutes. To ensure safety, visitors and residents should take precautions, particularly from April to August, by wearing protective clothing, applying broad-spectrum sunscreen regularly, and limiting direct sun exposure during peak hours.
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 |
| Onagawa Cho | 3 | 4 | 6 | 8 | 10 | 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 |