UV Index in Isahaya, Japan

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.

Hourly UV Index in Isahaya

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.

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
TimeUVICategoryTime to Burn
07:002low45 min
08:003moderate30 min
09:006high25 min
10:008very high15 min
11:0010very high15 min
12:0011extreme10 min
13:0011extreme10 min
14:009very high15 min
15:007high25 min
16:004moderate30 min
17:002low45 min
18:001low45 min
19:001low45 min

Monthly UV Index Trends in Isahaya

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.

Monthly Maximum UV Index for Isahaya, Japan

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Isahaya. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec468111111121211864
Data source: Statistical UV Index data for Isahaya, based on information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

Compare Isahaya UV Index with Other Japan Cities

The table above highlights how UV exposure in Isahaya compares to other major locations across Japan. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.
Isahaya's solar exposure compared to other cities in Japan. Generated using Copernicus Atmosphere Monitoring Service information.
 JanFebMarAprMayJunJulAugSepOctNovDec
Sapporo UVI2367999108532
Yokohama UVI35891111111110754
Tokyo UVI35891111111110754
Nagoya UVI468101111111110753
Osaka UVI468111111121110753
Isahaya468111111121211864