UV Index in Kosai, Japan

Last updated: May 3, 2025

In the vibrant city of Kosai, Japan, being aware of the UV Index is essential for safeguarding your skin and overall health. With UV levels peaking at 11 during the day, understanding these fluctuations helps you take proactive measures against sunburn and long-term skin damage. Kosai's Cfa climate brings warm summers with high solar radiation, making it crucial to monitor UV exposure, especially during midday hours. Stay informed and protect yourself from the sun’s powerful rays to enjoy the beautiful outdoors safely!

Hourly UV Index in Kosai

The UV Index (UVI) exhibits a notable pattern throughout the day. Starting at 2 at 7:00 AM, it gradually rises, peaking at 11 by noon and 1:00 PM. This high level of UV exposure indicates that sun protection is essential during these hours. As the afternoon progresses, the UVI begins to dip, dropping to 7 by 2:00 PM and then declining further to 5 by 3:00 PM. By late afternoon, the sunlight's intensity reduces significantly, with the UVI falling to 1 by 5:00 PM and remaining minimal through 6:00 PM and 7:00 PM. This data underscores the importance of taking precautions during peak hours while enjoying the outdoors.

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	7	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	7	high	25 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 Kosai

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 Kosai, Japan

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

The table above highlights how UV exposure in Kosai 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.

Kosai'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
Kosai	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