September Weather in Tomakomai, Japan

Last updated: August 23, 2025

In Tomakomai, Japan, the average temperature in September hovers around 18°C (64°F), with occasional dips to a chilly 8°C (47°F) and peaks reaching a warm 26°C (80°F). Expect 145 mm (5.7 in) of precipitation over 15 days, contributing to a notably high humidity level of 88%. Enjoy the cozy weather, but be prepared for the rain!

September Temperature in Tomakomai

In September in Tomakomai, the average temperature is 18°C (64°F). The maximum can reach 26°C (80°F) and the minimum can be as low as 8°C (47°F). This makes it an ideal time for travelers to enjoy a pleasant mix of mild warm days and cooler evenings.

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

The chart illustrates September temperature patterns in Tomakomai, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Tomakomai, September typically has an average temperature of 18°C (64°F), with highs reaching up to 26°C (80°F) and lows dropping to around 8°C (47°F).

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

September Precipitation in Tomakomai

In Tomakomai in September, the precipitation amount is 145 mm (5.7 in) spread over the course of 15 days.

September Precipitation Trends in Tomakomai

The chart displays monthly precipitation patterns in Tomakomai, 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 Tomakomai, September typically receives around 145 mm (5.7 inches) of precipitation spread over approximately 15 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 Tomakomai

In Tomakomai in September, humidity is 88%. With an average temperature of 18°C (64°F), this humidity feels like you’re walking through a warm, enveloping mist, making every step slightly weighted but also refreshing, ideal for leisurely exploration but challenging for strenuous activities.

September Average Humidity in Tomakomai

This chart illustrates the average monthly humidity levels in Tomakomai, 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 Tomakomai is approximately 88%, 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 Tomakomai

In Tomakomai in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Tomakomai.

Maximum UV Index Levels in Tomakomai for September

The chart shows the monthly maximum UV Index (UVI) for Tomakomai 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 Tomakomai typically reaches 8, which falls under the very high exposure category.

Data source: Tomakomai 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 Tomakomai Compares to Other Months

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

This table compares monthly weather conditions in Tomakomai, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	49 mm (1.9 inches)	84%	low
February Weather	-4°C (26°F)	53 mm (2.1 inches)	83%	moderate
March Weather	1°C (34°F)	89 mm (3.5 inches)	81%	moderate
April Weather	5°C (42°F)	93 mm (3.7 inches)	81%	high
May Weather	11°C (51°F)	90 mm (3.6 inches)	86%	very high
June Weather	14°C (58°F)	128 mm (5.1 inches)	87%	very high
July Weather	19°C (66°F)	121 mm (4.7 inches)	93%	very high
August Weather	20°C (69°F)	206 mm (8.1 inches)	95%	very high
September Weather	18°C (64°F)	145 mm (5.7 inches)	88%	very high
October Weather	12°C (54°F)	143 mm (5.6 inches)	83%	moderate
November Weather	6°C (42°F)	102 mm (4.0 inches)	79%	moderate
December Weather	-1°C (30°F)	62 mm (2.4 inches)	80%	low