September Weather in Isen, Japan

Last updated: August 23, 2025

In September, the average temperature in Isen, Japan reaches a warm 28°C (82°F), with a comfortable minimum of 24°C (75°F) and a peak of 30°C (86°F). Expect 211 mm (8.3 in) of precipitation over 20 days, contributing to an average humidity of 82%. Enjoy the warm, humid charm of this locale!

September Temperature in Isen

In September in Isen, the average temperature is 28°C (82°F). The maximum can reach 30°C (86°F), and the minimum can be as low as 24°C (75°F). This pleasant climate makes it an ideal time for outdoor activities and exploring the local attractions.

September Weather in Isen: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Isen, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Isen, September typically has an average temperature of 28°C (82°F), with highs reaching up to 30°C (86°F) and lows dropping to around 24°C (75°F).

Data source: Temperature data for Isen generated using information from the Copernicus Climate Change Service.

September Precipitation in Isen

In Isen in September, the total precipitation amount is 211 mm (8.3 in) over the course of 20 days.

September Precipitation Trends in Isen

The chart displays monthly precipitation patterns in Isen, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Isen, September typically receives around 211 mm (8.3 inches) of precipitation spread over approximately 20 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in Isen

In Isen in September humidity is 82%. With an average temperature of 28°C (82°F), this humidity feels like walking through a warm, dense blanket, making outdoor activities a challenge and necessitating frequent breaks to stay hydrated.

September Average Humidity in Isen

This chart illustrates the average monthly humidity levels in Isen, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Isen is approximately 82%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Isen

In Isen in September, the maximum UV index is 12, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, underscoring the importance of sun protection. For detailed information, you can check the Hourly UV Index in Isen.

Maximum UV Index Levels in Isen for September

The chart shows the monthly maximum UV Index (UVI) for Isen in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Isen typically reaches 12, which falls under the extreme exposure category.

Data source: Isen September UVI data generated using 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.

How September Weather in Isen Compares to Other Months

Weather in Isen varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Isen, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Isen, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	17°C (63°F)	109 mm (4.3 inches)	71%	high
February Weather	17°C (63°F)	117 mm (4.6 inches)	71%	very high
March Weather	19°C (66°F)	153 mm (6.0 inches)	76%	extreme
April Weather	20°C (69°F)	114 mm (4.5 inches)	82%	extreme
May Weather	23°C (74°F)	192 mm (7.5 inches)	84%	extreme
June Weather	26°C (78°F)	456 mm (17.9 inches)	86%	extreme
July Weather	28°C (82°F)	208 mm (8.2 inches)	86%	extreme
August Weather	28°C (83°F)	150 mm (5.9 inches)	82%	extreme
September Weather	28°C (82°F)	211 mm (8.3 inches)	82%	extreme
October Weather	25°C (78°F)	137 mm (5.4 inches)	80%	very high
November Weather	22°C (72°F)	130 mm (5.1 inches)	79%	very high
December Weather	19°C (66°F)	127 mm (5.0 inches)	75%	high