UV Index in Isesaki, Japan

Last updated: July 2, 2025

In Isesaki, Japan, understanding the UV Index is crucial for maintaining healthy skin and preventing sunburn. With a humid subtropical climate (Cfa), the city experiences significant UV exposure, especially during the peak hours of 11:00 AM to 1:00 PM, when the UV Index can soar to an impressive 11. Being aware of these levels allows residents and visitors alike to take necessary precautions to protect themselves, ensuring safe outdoor enjoyment while minimizing risks associated with harmful ultraviolet radiation. Stay informed about the daily UV Index to safeguard your skin health and revel in the beauty of Isesaki!

Hourly UV Index in Isesaki

The hourly UV Index reveals a dynamic rise and fall of sun intensity throughout the day. Starting at a mild 2 at 07:00, the index climbs steadily, reaching a peak of 11 at both 11:00 and 12:00, indicating a high risk of harm from unprotected sun exposure. As the afternoon sun begins to descend, the index tapers off to 9 at 13:00, then gradually decreases to 5 by 15:00. By 16:00, it drops to 3, signaling the end of peak sun strength, while cool evenings arrive with a return to 1 at both 17:00 and 18:00. Finally, at 19:00, the UV Index hits 0, marking a safe transition into the night. Stay protected during the day's brightest 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	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	9	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 Isesaki

Throughout the year, UV levels demonstrate significant seasonal variations, with high-risk months typically occurring from March through August. During this period, the UV Index peaks at 11 in June, July, and August, marking it as an extreme risk category with a burn time of just 10 minutes. In contrast, the lowest UV Index readings, categorized as moderate, occur in January, February, November, and December, allowing for 30-minute exposure without immediate risk of skin damage. Visitors and residents should prioritize sun safety measures, particularly in the high-risk months—using sunscreen, wearing protective clothing, and seeking shade during peak hours to minimize potential harm from intense UV radiation.

Monthly Maximum UV Index for Isesaki, Japan

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

The table above highlights how UV exposure in Isesaki 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.

Isesaki'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
Isesaki	3	5	8	9	10	11	11	11	9	7	5	3
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