December Weather in Rumoi, Japan

Last updated: August 23, 2025

In Rumoi, Japan, the average temperature in December hovers around -2°C (28°F), with the minimum dipping to a frosty -16°C (4°F) and peaking at a mild 12°C (54°F). Expect considerable precipitation, averaging 132 mm (5.2 in) over 27 days, accompanied by a high humidity level of 80%. Prepare for a chilly and damp month ahead!

December Temperature in Rumoi

In December in Rumoi, the average temperature is -2°C (28°F). The maximum can reach 12°C (54°F), while the minimum can plummet to as low as -16°C (4°F). Travelers should be prepared for brisk, cold weather and dress in layers to stay warm during their visit.

December Weather in Rumoi: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Rumoi, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Rumoi, December typically has an average temperature of -2°C (28°F), with highs reaching up to 12°C (54°F) and lows dropping to around -16°C (4°F).

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

December Precipitation in Rumoi

In Rumoi in December, the precipitation amount is 132 mm (5.2 in) spread over 27 days.

December Precipitation Trends in Rumoi

The chart displays monthly precipitation patterns in Rumoi, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Rumoi, December typically receives around 132 mm (5.2 inches) of precipitation spread over approximately 27 days.

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

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Millimeters (mm) Inches (in)

December Humidity in Rumoi

In Rumoi in December, humidity is 80%. With an average temperature of -2°C (28°F), this humidity feels like a sharp, biting chill that seeps into your bones, making outdoor exploration uncomfortable and necessitating extra layers to ward off the damp cold.

December Average Humidity in Rumoi

This chart illustrates the average monthly humidity levels in Rumoi, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Rumoi is approximately 80%, offering insight into how humid the weather typically is during this month.

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

December UV Index in Rumoi

In Rumoi in December, the maximum UV index is 2, which corresponds to a low exposure category. With this level of UV radiation, the time to burn is approximately 45 minutes. To learn more about the hourly UV index in Rumoi, you can visit Hourly UV Index in Rumoi.

Maximum UV Index Levels in Rumoi for December

The chart shows the monthly maximum UV Index (UVI) for Rumoi in December, 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 December, the maximum UV index in Rumoi typically reaches 2, which falls under the low exposure category.

Data source: Rumoi December 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 December Weather in Rumoi Compares to Other Months

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

This table compares monthly weather conditions in Rumoi, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-5°C (22°F)	70 mm (2.8 inches)	84%	low
February Weather	-4°C (24°F)	84 mm (3.3 inches)	83%	moderate
March Weather	0°C (33°F)	84 mm (3.3 inches)	81%	moderate
April Weather	6°C (42°F)	67 mm (2.6 inches)	81%	high
May Weather	11°C (52°F)	89 mm (3.5 inches)	86%	very high
June Weather	15°C (59°F)	94 mm (3.7 inches)	87%	very high
July Weather	21°C (69°F)	103 mm (4.0 inches)	93%	very high
August Weather	21°C (70°F)	171 mm (6.7 inches)	95%	very high
September Weather	18°C (64°F)	90 mm (3.6 inches)	88%	very high
October Weather	12°C (53°F)	147 mm (5.8 inches)	83%	moderate
November Weather	5°C (41°F)	152 mm (6.0 inches)	79%	moderate
December Weather	-2°C (28°F)	132 mm (5.2 inches)	80%	low