September Weather in Arai, Japan

Last updated: August 23, 2025

In September, the average temperature in Arai, Japan hovers around 20°C (69°F), but can range from a cool 10°C (50°F) to a sweltering 33°C (92°F). Expect some rain, with 207 mm (8.2 in) of precipitation spread over 18 days. Additionally, the average humidity is quite high at 89%, making it feel even warmer!

September Temperature in Arai

In September in Arai, the average temperature is 20°C (69°F). Maximums can reach 33°C (92°F), and minimums can be as low as 10°C (50°F). This makes it a comfortable destination for travelers looking for mild weather while exploring.

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

The chart illustrates September temperature patterns in Arai, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Arai, September typically has an average temperature of 20°C (69°F), with highs reaching up to 33°C (92°F) and lows dropping to around 10°C (50°F).

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

September Precipitation in Arai

In Arai in September, the total precipitation amount is 207 mm (8.2 in) recorded over the course of 18 days.

September Precipitation Trends in Arai

The chart displays monthly precipitation patterns in Arai, 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 Arai, September typically receives around 207 mm (8.2 inches) of precipitation spread over approximately 18 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Arai

In Arai in September humidity is 89%. With an average temperature of 20°C (69°F), this humidity feels like a warm blanket enveloping you, making outdoor activities uncomfortable and requiring frequent breaks for hydration and rest.

September Average Humidity in Arai

This chart illustrates the average monthly humidity levels in Arai, 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 Arai is approximately 89%, 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 Arai

In Arai in September, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Arai.

Maximum UV Index Levels in Arai for September

The chart shows the monthly maximum UV Index (UVI) for Arai 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 Arai typically reaches 9, which falls under the very high exposure category.

Data source: Arai 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 Arai Compares to Other Months

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

This table compares monthly weather conditions in Arai, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	0°C (32°F)	227 mm (8.9 inches)	88%	moderate
February Weather	0°C (33°F)	188 mm (7.4 inches)	86%	moderate
March Weather	4°C (40°F)	149 mm (5.8 inches)	81%	very high
April Weather	9°C (49°F)	146 mm (5.8 inches)	78%	very high
May Weather	16°C (60°F)	152 mm (6.0 inches)	81%	very high
June Weather	19°C (66°F)	173 mm (6.8 inches)	88%	extreme
July Weather	23°C (75°F)	353 mm (13.9 inches)	92%	extreme
August Weather	25°C (77°F)	210 mm (8.3 inches)	92%	extreme
September Weather	20°C (69°F)	207 mm (8.2 inches)	89%	very high
October Weather	15°C (59°F)	235 mm (9.3 inches)	87%	high
November Weather	8°C (48°F)	144 mm (5.7 inches)	85%	moderate
December Weather	2°C (37°F)	247 mm (9.7 inches)	86%	moderate