September Weather in Omi, Japan

Last updated: August 23, 2025

In September, the average temperature in Omi, Japan hovers around 19°C (66°F). However, it's good to prepare for a range—from a chilly 6°C (43°F) at the lowest to a warm 30°C (86°F) at the highest. Expect 285 mm (11.2 in) of precipitation spread across 22 days, combined with an average humidity of 89%, making the air feel quite moist.

September Temperature in Omi

In September in Omi, the average temperature is 19°C (66°F). The maximum can reach 30°C (86°F) and the minimum can be as low as 6°C (43°F). This makes it a great time to explore Omi, with comfortable weather for outdoor activities and sightseeing.

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

The chart illustrates September temperature patterns in Omi, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Omi, September typically has an average temperature of 19°C (66°F), with highs reaching up to 30°C (86°F) and lows dropping to around 6°C (43°F).

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

September Precipitation in Omi

In Omi in September, the precipitation amount is 285 mm (11.2 in) over the course of 22 days.

September Precipitation Trends in Omi

The chart displays monthly precipitation patterns in Omi, 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 Omi, September typically receives around 285 mm (11.2 inches) of precipitation spread over approximately 22 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 Omi

In Omi in September humidity is 89%. With an average temperature of 19°C (66°F), this humidity feels like walking through a damp blanket, making every step more laborious and the air thick, potentially leading to discomfort while exploring or sightseeing.

September Average Humidity in Omi

This chart illustrates the average monthly humidity levels in Omi, 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 Omi 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 Omi

In Omi 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 Omi.

Maximum UV Index Levels in Omi for September

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

Data source: Omi 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 Omi Compares to Other Months

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

This table compares monthly weather conditions in Omi, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-3°C (27°F)	151 mm (6.0 inches)	88%	moderate
February Weather	-2°C (29°F)	138 mm (5.4 inches)	86%	high
March Weather	3°C (38°F)	172 mm (6.8 inches)	81%	very high
April Weather	8°C (47°F)	182 mm (7.2 inches)	78%	very high
May Weather	14°C (58°F)	227 mm (8.9 inches)	81%	extreme
June Weather	18°C (64°F)	256 mm (10.1 inches)	88%	extreme
July Weather	22°C (72°F)	437 mm (17.2 inches)	92%	extreme
August Weather	23°C (74°F)	276 mm (10.9 inches)	92%	extreme
September Weather	19°C (66°F)	285 mm (11.2 inches)	89%	very high
October Weather	13°C (55°F)	277 mm (10.9 inches)	87%	high
November Weather	6°C (44°F)	119 mm (4.7 inches)	85%	moderate
December Weather	0°C (33°F)	163 mm (6.4 inches)	86%	moderate