Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Chonan, Japan, where sun exposure can vary significantly throughout the day. Being aware of UV levels not only aids in preventing sunburn but also plays a vital role in protecting skin health over the long term. Chonan's Cfa climate brings warm summers and ample sunshine, resulting in higher UV risks, particularly during the midday hours when the index peaks at 11. By staying informed about daily UV trends, you can enjoy the outdoors safely while minimizing the risks associated with sun exposure.
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 |
Chonan | 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 |