UV Index in Oshima, Japan

Last updated: August 1, 2025

In Oshima, Japan, being aware of the UV Index is crucial for protecting your skin and overall health against harmful sun exposure. Understanding UV levels helps in preventing sunburn and reducing the long-term risks of skin cancer, especially with the island's warm Cfa climate that promotes high UV exposure, particularly during peak hours. With the UV Index reaching a high of 12 around noon, it’s essential for residents and visitors alike to stay informed and take the necessary precautions to enjoy the sun safely. Embrace the beauty of Oshima while keeping your skin safe!

Hourly UV Index in Oshima

As the sun ascends, the UV Index reflects a dynamic shift in solar intensity. Early risers at 7:00 AM will notice a moderate level of 2, scaling up to 4 by 8:00 AM. The sun reaches its peak intensity between 11:00 AM and 12:00 PM, with a startling high of 12, urging sunbathers to seek shade or sunscreen. After noon, the index gradually declines, dropping to 10 at 1:00 PM and tapering off further to 5 by 3:00 PM. As the day wanes, the UV levels diminish to a gentle 1 by 5:00 PM, finally settling at 0 after 7:00 PM. Always be mindful of these fluctuations to protect your skin effectively!

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.
Time	UVI	Category	Time to Burn
07:00	2	low	45 min
08:00	4	moderate	30 min
09:00	6	high	25 min
10:00	9	very high	15 min
11:00	11	extreme	10 min
12:00	11	extreme	10 min
13:00	10	very high	15 min
14:00	8	very high	15 min
15:00	5	moderate	30 min
16:00	3	moderate	30 min
17:00	1	low	45 min
18:00	1	low	45 min
19:00	0	low	45 min

Monthly UV Index Trends in Oshima

The UV Index experiences significant seasonal variation, with March through September being the high-risk months for sun exposure. March begins the rise with an index of 8 (very high) and only a 15-minute burn time, peaking in July with an index of 12 (extreme) and a mere 10-minute burn time. May through August consistently holds an extreme exposure category, urging increased caution during these months. As summer transitions into fall, the index gradually decreases, with October dropping to 7 (high) and 15-minute burn times for October and September, before returning to moderate levels in winter. Visitors and residents are advised to take precautions during the high-risk months by seeking shade, wearing protective clothing, and applying sunscreen regularly to minimize the risk of skin damage.

Monthly Maximum UV Index for Oshima, Japan

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Oshima. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.

Data source: Statistical UV Index data for Oshima, 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 Oshima UV Index with Other Japan Cities

The table above highlights how UV exposure in Oshima 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.

Oshima's solar exposure compared to other cities in Japan. Generated using Copernicus Atmosphere Monitoring Service information.
	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
Oshima	4	5	8	10	11	11	12	11	10	7	5	4
Osaka UVI	4	6	8	11	11	11	12	11	10	7	5	3