UV Index in Hojo, Japan

Last updated: August 1, 2025

Understanding the UV Index is crucial for residents and visitors of Hojo, Japan, as it directly impacts sun safety and skin health. The UV levels here can reach a staggering 12 during peak hours, highlighting the importance of protecting yourself from harmful UV radiation that can lead to sunburn and long-term skin damage. With Hojo’s Cfa climate, characterized by warm summers, the risk of overexposure increases significantly, particularly between 10 AM and 2 PM. By being aware of the UV Index, you can enjoy the beautiful outdoors while minimizing health risks associated with sun exposure.

Hourly UV Index in Hojo

The UV Index throughout the day showcases a dynamic shift in sun intensity, peaking at 12 around noon. Beginning with a gentle 2 at 7:00 AM, the index steadily increases, hitting 11 by 11:00 AM as the sun climbs higher. By 12:00 PM, the sun reaches its zenith at 12, marking the highest UV exposure, making sun safety a priority. As the afternoon progresses, from 1:00 PM to 3:00 PM, the UV Index gradually decreases to 9 by 2:00 PM and 7 by 3:00 PM. The day winds down with a notable drop in intensity, returning to a mild 1 by 6:00 PM, emphasizing that the safest time to enjoy the sun is before noon or after 4:00 PM.

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	1	low	45 min
08:00	3	moderate	30 min
09:00	6	high	25 min
10:00	8	very high	15 min
11:00	11	extreme	10 min
12:00	12	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	0	low	45 min

Monthly UV Index Trends in Hojo

The UV Index experiences significant seasonal fluctuations, peaking between May and August, where an extreme rating of 11 to 12 indicates a burn time of just 10 minutes. March and April also see heightened levels, categorized as very high with a burn time of 15 minutes. Conversely, the UV Index is at its lowest during January, February, and December, marked as moderate, allowing for a safer 30-minute exposure before risking sunburn. The highest-risk months for UV exposure are May to August, necessitating strong sun protection measures for visitors and residents alike. It is essential to wear sunscreen, protective clothing, and sunglasses, especially during peak hours, to minimize the risk of UV-related health issues.

Monthly Maximum UV Index for Hojo, Japan

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

The table above highlights how UV exposure in Hojo 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.

Hojo'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
Hojo	4	5	8	10	11	11	12	12	10	7	6	4