Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Yokaichiba, Japan, where the subtropical climate brings both warmth and potential sun exposure risks. Awareness of UV levels can significantly contribute to preventing sunburn and promoting skin health, especially during the peak hours of 10 AM to 2 PM when the index reaches levels 10 to 11—indicating a high risk of harm from unprotected sun exposure. With Yokaichiba's Cfa climate featuring warm summers, it's essential to recognize these high UV moments and take proactive measures to protect your skin from damage and enjoy the beautiful outdoors safely.
As the sun rises, the UV Index begins its ascent, starting at a modest 2 at 07:00. The real intensity kicks in by 10:00, peaking at an impressive 11 from 11:00 to 12:00, signaling the need for sun protection. After the midday sun, the index gradually declines, dipping to 4 by 15:00 before sliding down to 1 by 17:00. As the evening approaches, the UV rays fade to 0 by 19:00, marking a safe end to outdoor activities. This data underscores the importance of staying sun-safe during the peak hours!
Time | UVI | Category | Time to Burn |
---|---|---|---|
07:00 | 2 | low | 45 min |
08:00 | 5 | moderate | 30 min |
09:00 | 7 | high | 25 min |
10:00 | 10 | very high | 15 min |
11:00 | 11 | extreme | 10 min |
12:00 | 11 | extreme | 10 min |
13:00 | 9 | very high | 15 min |
14:00 | 7 | 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 levels display significant seasonal changes, with the highest readings occurring from May to August, where the index reaches an extreme level of 11. This period signifies a high-risk for UV exposure, with a dangerously quick burn time of only 10 minutes. In contrast, the winter months of January, February, November, and December feature moderate UV levels, with indices ranging from 3 to 5 and a burn time of 30 minutes or more. Visitors and residents should take precautions during the peak months, particularly by seeking shade, wearing protective clothing, and applying sunscreen, as skin damage can occur rapidly during this time. It's crucial to remain vigilant during the spring and early fall as well, when UV levels are still notably high, especially in 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 |
Yokaichiba | 3 | 5 | 8 | 9 | 11 | 11 | 11 | 11 | 9 | 7 | 5 | 4 |
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 |