September Weather in Oiso, Japan

Last updated: August 23, 2025

In September, the average temperature in Oiso, Japan is a pleasant 23°C (74°F), with minimums dipping to 17°C (63°F) and maximums soaring to 30°C (87°F). Expect heavy precipitation totaling 235 mm (9.3 in) over approximately 19 days, accompanied by an average humidity level of 86%. Ideal for those who enjoy a lush, tropical atmosphere!

September Temperature in Oiso

In September in Oiso, the average temperature is 23°C (74°F). Maximums can reach 30°C (87°F), and minimums can be as low as 17°C (63°F). This pleasant climate makes Oiso an ideal destination for travelers seeking enjoyable weather and outdoor activities.

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

The chart illustrates September temperature patterns in Oiso, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Oiso, September typically has an average temperature of 23°C (74°F), with highs reaching up to 30°C (87°F) and lows dropping to around 17°C (63°F).

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

September Precipitation in Oiso

In Oiso in September, the precipitation amount is 235 mm (9.3 in) over the course of 19 days.

September Precipitation Trends in Oiso

The chart displays monthly precipitation patterns in Oiso, 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 Oiso, September typically receives around 235 mm (9.3 inches) of precipitation spread over approximately 19 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 Oiso

In Oiso in September, humidity is 86%. With an average temperature of 23°C (74°F), this humidity feels like you're stepping into a warm embrace, making travel a bit sticky yet invigorating, as the air wraps around you, inviting you to explore while reminding you to stay hydrated.

September Average Humidity in Oiso

This chart illustrates the average monthly humidity levels in Oiso, 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 Oiso is approximately 86%, 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 Oiso

In Oiso in September, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Oiso.

Maximum UV Index Levels in Oiso for September

The chart shows the monthly maximum UV Index (UVI) for Oiso 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 Oiso typically reaches 10, which falls under the very high exposure category.

Data source: Oiso 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 Oiso Compares to Other Months

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

This table compares monthly weather conditions in Oiso, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	7°C (44°F)	69 mm (2.7 inches)	76%	moderate
February Weather	7°C (45°F)	75 mm (3.0 inches)	74%	moderate
March Weather	10°C (51°F)	195 mm (7.7 inches)	70%	very high
April Weather	13°C (57°F)	162 mm (6.4 inches)	74%	very high
May Weather	18°C (64°F)	166 mm (6.5 inches)	81%	extreme
June Weather	21°C (70°F)	224 mm (8.8 inches)	88%	extreme
July Weather	24°C (76°F)	263 mm (10.3 inches)	93%	extreme
August Weather	26°C (80°F)	159 mm (6.2 inches)	90%	extreme
September Weather	23°C (74°F)	235 mm (9.3 inches)	86%	very high
October Weather	19°C (66°F)	346 mm (13.6 inches)	83%	high
November Weather	14°C (58°F)	115 mm (4.5 inches)	80%	moderate
December Weather	9°C (49°F)	91 mm (3.6 inches)	78%	moderate