UV Index in Aka, Japan

Last updated: May 3, 2025

In Aka, Japan, understanding the UV Index is crucial for protecting your skin and preventing sunburn, as the region experiences a humid subtropical climate (Cfa) with intense sunlight, especially during summer months. As UV levels can peak at an alarming 11 around midday, being aware of these levels helps residents and visitors take proactive measures to safeguard their skin health. With UVA and UVB rays posing significant risks throughout the day, from sunburn to long-term skin damage, keeping an eye on the UV Index can make all the difference in enjoying outdoor activities safely while minimizing harmful exposure.

Hourly UV Index in Aka

The UV Index today showcases a dynamic rise and fall throughout the hours, peaking at 11 from 12:00 PM to 1:00 PM. Starting from a gentle 2 at 7:00 AM, it climbs steadily, reaching 10 by 11:00 AM. As the sun approaches its zenith, the index hits its maximum of 11, indicating a high risk of harm from unprotected sun exposure. After this peak, the index begins its descent, tapering down to 6 at 3:00 PM before declining further to 2 by 5:00 PM. As evening sets in, it settles at a mild 1 from 6:00 PM onward, reminding us to take precautions when basking in the midday sun but allowing for safer outdoor activities as daylight fades.

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	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	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 Aka

Throughout the year, seasonal changes in UV exposure highlight periods of heightened risk for residents and visitors. From January to February, the UV Index rises from 4 (moderate) to 6 (high), reducing safe exposure time to 25 minutes. Significant increases occur in March, reaching 8 (very high), and peaking during the summer months of April to August at 11-12 (extreme), where only 10 minutes of unprotected exposure is advisable. The risk, while still present, decreases again in September and returns to high levels in October and November with a UV Index of 6-7, allowing for 25 minutes of safe exposure. As such, it is crucial for visitors and residents to remain vigilant, especially during the summer, taking precautions like wearing sunscreen, protective clothing, and seeking shade during peak hours to mitigate the risk of UV-related health issues.

Monthly Maximum UV Index for Aka, Japan

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

The table above highlights how UV exposure in Aka 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.

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