UV Index in Innoshima, Japan

Last updated: June 2, 2025

Understanding the UV Index is crucial for residents and visitors in Innoshima, Japan, where the sun's rays can be deceptively intense. With a Cfa climate characterized by warm summers, awareness of UV levels helps prevent sunburn and promotes long-term skin health. During peak hours, especially around noon when the UV Index reaches a maximum of 11, the risk of harmful exposure increases significantly, making it essential to take protective measures. By keeping an eye on the UV Index, you can enjoy the beautiful outdoors of Innoshima while safeguarding your skin from potential damage.

Hourly UV Index in Innoshima

The UV Index paints a vivid picture of the sun’s strength throughout the day. Starting at a modest 2 at 07:00, the index gradually climbs as the sun ascends, reaching 4 by 08:00. By 09:00, it spikes to 6, and before long, it peaks at an impressive 11 at 12:00, marking the most intense exposure. The afternoon starts to cool slightly, with the index dropping to 10 by 13:00 and then tapering off through 8 at 14:00, 6 at 15:00, and back to 4 at 16:00. As the sun begins its descent, the UV Index falls to 2 by 17:00, lingering at 1 through the evening hours, creating a gentle reminder to enjoy the sun but also to stay mindful of its intensity during 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.
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	8	very high	15 min
11:00	10	very high	15 min
12:00	11	extreme	10 min
13:00	10	very high	15 min
14:00	8	very high	15 min
15:00	6	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

Monthly UV Index Trends in Innoshima

The UV Index experiences significant seasonal fluctuations, peaking between May and August, where an extreme rating of 11 to 12 indicates a burn time of just 10 minutes. March and April also see heightened levels, categorized as very high with a burn time of 15 minutes. Conversely, the UV Index is at its lowest during January, February, and December, marked as moderate, allowing for a safer 30-minute exposure before risking sunburn. The highest-risk months for UV exposure are May to August, necessitating strong sun protection measures for visitors and residents alike. It is essential to wear sunscreen, protective clothing, and sunglasses, especially during peak hours, to minimize the risk of UV-related health issues.

Monthly Maximum UV Index for Innoshima, Japan

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Innoshima. 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 Innoshima, 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 Innoshima UV Index with Other Japan Cities

The table above highlights how UV exposure in Innoshima 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.

Innoshima'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
Innoshima	4	5	8	10	11	11	12	12	10	7	6	4
Osaka UVI	4	6	8	11	11	11	12	11	10	7	5	3