UV Index in Suwa, Japan

Last updated: May 3, 2025

In Suwa, Japan, being aware of the UV Index is essential for protecting your skin and maintaining overall health. Understanding UV levels can help you prevent sunburn and reduce the risk of long-term skin damage, making it crucial for outdoor enthusiasts and casual sunbathers alike. With Suwa's Dfb climate, characterized by warm summers and moderate sun exposure, UV levels can reach significant highs—peaking at 11 during midday hours. By keeping an eye on the UV Index, you can make informed decisions to enjoy the sun safely while safeguarding your skin.

Hourly UV Index in Suwa

The UV Index throughout the day reveals a dramatic rise in sun intensity, peaking at 11 around 11:00 AM and 12:00 PM. Starting from 07:00 AM with a low of 2, the index escalates rapidly, reaching 10 by 10:00 AM. As the sun climbs higher, it delivers its harshest rays, prompting caution for those outdoors. From 1:00 PM onward, the index gradually declines, hitting 5 at 3:00 PM, and finally tapering off to 0 by 7:00 PM. This profile highlights the importance of sun protection during the midday hours when UV exposure is most intense. Stay safe and protect your skin! 🌞

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	5	moderate	30 min
09:00	7	high	25 min
10:00	10	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 Suwa

Throughout the year, UV index levels fluctuate, with the most significant increases occurring from March to September. During these months, particularly in May, June, July, and August, the UV index reaches its peak at 12, categorized as extreme, with a burn time of just 10 minutes. March and April also present high risks, featuring very high UV levels of 9 and 10 respectively. Visitors and residents should be particularly vigilant in these high-risk months, applying sunscreen, wearing protective clothing, and seeking shade whenever possible. As UV levels decrease from late summer into fall and winter, with January and December categorized as having moderate exposure (UV index 4), precautions remain advisable to ensure skin protection year-round.

Monthly Maximum UV Index for Suwa, Japan

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

The table above highlights how UV exposure in Suwa 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.

Suwa'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
Suwa	4	6	9	10	11	11	12	12	10	7	5	4