UV Index in Hayashima, Japan

Last updated: May 3, 2025

In Hayashima, Japan, understanding the UV Index is crucial for protecting your skin from harmful UV rays, especially given the region's Cfa climate characterized by warm summers. As the sun's intensity peaks, particularly between 10:00 AM and 2:00 PM when the UV Index reaches a maximum of 11, it's important to be aware of the risks of sunburn and long-term skin damage. By tracking UV levels, residents and visitors can take proactive steps to safeguard their health and enjoy the beautiful outdoors while minimizing exposure during those high-risk hours.

Hourly UV Index in Hayashima

The UV Index early in the day starts off modest, peaking at 2 by 07:00 and climbing to a moderate 3 by 08:00. By 09:00, it surges to a robust 6, indicating increasing sun intensity. The heat reaches its zenith at 12:00, hitting an impressive 11, showing that midday is the prime time for sun exposure. As the afternoon progresses, the UV Index gradually declines, falling to 10 at 13:00, then to 8 by 14:00. By late afternoon, 15:00 sees it drop to 6, and as the sun sets, the index continues to taper off, descending to 3 by 16:00, and eventually settling at a low 0 by 19:00. It’s a day that underscores the importance of sun protection during peak hours, especially around noon.

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	10	very high	15 min
14:00	8	very high	15 min
15:00	6	high	25 min
16:00	3	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 Hayashima

From January to December, UV Index values exhibit significant seasonal changes, peaking during the summer months. January and December maintain a moderate UV Index of 4, allowing for a burn time of 30 minutes. As spring arrives, March sees a notable increase to 8 (very high), reducing burn time to 15 minutes. The peak UV exposure occurs from May through August, where the index reaches a maximum of 12 (extreme), necessitating a burn time as brief as 10 minutes. September begins a gradual decline, returning to a very high level of 10, while October and November drop to moderate levels at 5. Visitors and residents should exercise caution from March to August, particularly during these high-risk months, by wearing protective clothing, applying sunscreen frequently, and seeking shade to limit UV exposure.

Monthly Maximum UV Index for Hayashima, Japan

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

The table above highlights how UV exposure in Hayashima 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.

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