UV Index in Nakano, Japan

Last updated: July 2, 2025

Understanding the UV Index in Nakano, Japan, is crucial for safeguarding your skin and overall health. This helpful metric, which ranges from 0 to 11 throughout the day, informs residents about the intensity of ultraviolet (UV) rays and underscores the importance of sunburn prevention. In Nakano's humid continental climate, where UV levels peak at midday, awareness of these changes can make a significant difference in protecting against skin damage. With UV index values soaring to 11 during the late morning and early afternoon, knowing when to seek shade or apply sunscreen is vital for maintaining skin health and enjoying the beautiful outdoor spaces of Nakano safely.

Hourly UV Index in Nakano

The UV Index throughout the day presents a dynamic picture of sun exposure. As early as 7:00 AM, the index starts at a mild 2, ramping up to a moderate 4 by 8:00 AM. The sun's intensity peaks around 11:00 AM and 12:00 PM with a striking 11, marking the height of caution for outdoor activities. As we move into the afternoon, the index gradually declines, dropping to 8 by 2:00 PM and further to 5 by 3:00 PM. The evening brings relief, with the UV Index decreasing to a 1 by 5:00 PM and finally hitting 0 by 7:00 PM. It’s clear that the midday hours pose the greatest risk, so sun safety measures are essential during those peak times.

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	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 Nakano

Throughout the year, UV radiation levels fluctuate significantly, impacting exposure risks for visitors and residents. The high-risk months for UV exposure are March through August, where the UV Index reaches very high to extreme levels, particularly peaking at an Index of 11 during May to August, allowing for a burn time of just 10 minutes. In contrast, the moderate UV conditions in January, November, and December allow for longer burn times of 30 minutes but still require caution. Visitors and residents should take appropriate precautions, such as wearing sunscreen, protective clothing, and sunglasses, especially during high UV months, to minimize the risk of skin damage.

Monthly Maximum UV Index for Nakano, Japan

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

The table above highlights how UV exposure in Nakano 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.

Nakano'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
Nakano	4	6	9	9	11	11	11	11	10	7	5	3
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