Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors in Okawa, Japan, where the warm Cfa climate can lead to elevated UV exposure, especially during the summer months. With peaks reaching as high as 12 in midday hours, awareness of these levels is essential for effective sunburn prevention and maintaining long-term skin health. By keeping track of the UV Index, you can better protect yourself and your loved ones from harmful UV rays that can cause skin damage and increase the risk of skin cancer. Stay informed to enjoy the beautiful outdoors while safeguarding your skin!
During the morning hours, the UV Index starts off low at 1 at 7:00 AM, indicating minimal risk of harm from unprotected sun exposure. As the day progresses, the intensity ramps up, peaking at 12 around 12:00 PM and 1:00 PM, suggesting a high risk for harm, especially for those spending extended periods outdoors. Post-peak, the index gradually declines, dropping to 7 at 3:00 PM and further down to 1 by 7:00 PM, which indicates a return to minimal risk as the sun sets. For sun enthusiasts, midday offers the most intense UV radiation, making sun protection essential during those hours!
Time | UVI | Category | Time to Burn |
---|---|---|---|
07:00 | 1 | low | 45 min |
08:00 | 3 | moderate | 30 min |
09:00 | 6 | high | 25 min |
10:00 | 9 | very high | 15 min |
11:00 | 11 | extreme | 10 min |
12:00 | 12 | extreme | 10 min |
13:00 | 12 | extreme | 10 min |
14:00 | 10 | very high | 15 min |
15:00 | 7 | 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 |
Okawa | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 12 | 11 | 7 | 6 | 4 |