Last updated: June 2, 2025
In Isahaya, Japan, awareness of the UV Index is crucial for maintaining skin health and preventing sunburn, especially during the warm summer months. Understanding UV levels helps residents and visitors alike protect themselves against harmful ultraviolet radiation, which can lead to short-term discomfort and long-term skin issues. Isahaya's Cfa climate brings a mix of humidity and sunshine, leading to higher UV exposure, particularly from late morning to early afternoon when levels peak at 11. Staying informed about the UV Index is essential for enjoying the outdoors safely while safeguarding your skin.
The UV Index throughout the day presents a notable peak between 11:00 AM and 1:00 PM, where it reaches a striking 11, indicating a high risk for harm from unprotected sun exposure. The intensity starts at a lower 2 at 7:00 AM, gradually climbing to 3 by 8:00 AM before skyrocketing to 10 by 11:00 AM. As the midday sun intensifies, it maintains a level of 11 at both 12:00 PM and 1:00 PM, prompting a reminder to seek shade and wear protective gear. The afternoon sees a decline, dipping to 9 at 2:00 PM and gradually tapering off to 4 by 4:00 PM, then further down to 2 at 5:00 PM. As evening approaches, the levels drop to a gentle 1 by 6:00 PM, highlighting the importance of being sun-aware, especially during those peak hours.
Time | UVI | Category | Time to Burn |
---|---|---|---|
07:00 | 2 | low | 45 min |
08:00 | 3 | moderate | 30 min |
09:00 | 6 | high | 25 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 | 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, the UV Index exhibits significant seasonal variations, with spring and summer months posing the highest risk of UV exposure. From March to September, the index reaches very high to extreme levels—particularly during April to August, where it peaks at 12 in July and August. During these months, the burn time shortens dramatically to just 10 minutes, indicating a critical need for sun protection. Conversely, January and December record the lowest UV levels with a moderate exposure category, allowing for more extended exposure times of 30 minutes. Visitors and residents are advised to take precautions, especially from March to September, by wearing protective clothing, applying sunscreen, and seeking shade during peak hours to minimize the risks associated with high UV exposure.
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 |
Isahaya | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 12 | 11 | 8 | 6 | 4 |