December Weather in Umi, Japan

Last updated: August 23, 2025

In December, the average temperature in Umi, Japan hovers around 8°C (46°F). Expect a chilly minimum of -1°C (31°F), with highs reaching up to 23°C (73°F). This month typically sees around 68 mm (2.7 in) of precipitation spread over 8 days, contributing to a comfortable average humidity of 79%.

December Temperature in Umi

In December in Umi, the average temperature is 8°C (46°F). The maximum can reach 23°C (73°F) and the minimum can be as low as -1°C (31°F). Pack accordingly for a mix of cool days and warmer afternoons, perfect for outdoor activities and sightseeing.

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

The chart illustrates December temperature patterns in Umi, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Umi, December typically has an average temperature of 8°C (46°F), with highs reaching up to 23°C (73°F) and lows dropping to around -1°C (31°F).

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

December Precipitation in Umi

In Umi in December, the precipitation amount is 68 mm (2.7 in) spread over 8 days.

December Precipitation Trends in Umi

The chart displays monthly precipitation patterns in Umi, 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 Umi, December typically receives around 68 mm (2.7 inches) of precipitation spread over approximately 8 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 Umi

In Umi in December humidity is 79%. With an average temperature of 8°C (46°F), this humidity feels like a damp chill that seeps into your bones, making outdoor activities a bit less enjoyable and leading travelers to seek cozy, warm spots to regain their comfort.

December Average Humidity in Umi

This chart illustrates the average monthly humidity levels in Umi, 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 Umi is approximately 79%, 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 Umi

In Umi in December, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in Umi for better planning.

Maximum UV Index Levels in Umi for December

The chart shows the monthly maximum UV Index (UVI) for Umi 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 Umi typically reaches 4, which falls under the moderate exposure category.

Data source: Umi 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 Umi Compares to Other Months

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

This table compares monthly weather conditions in Umi, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	6°C (43°F)	58 mm (2.3 inches)	75%	moderate
February Weather	7°C (45°F)	80 mm (3.1 inches)	71%	high
March Weather	11°C (52°F)	121 mm (4.8 inches)	71%	very high
April Weather	15°C (59°F)	115 mm (4.5 inches)	78%	extreme
May Weather	20°C (68°F)	163 mm (6.4 inches)	84%	extreme
June Weather	23°C (74°F)	199 mm (7.8 inches)	86%	extreme
July Weather	27°C (81°F)	367 mm (14.4 inches)	92%	extreme
August Weather	28°C (83°F)	303 mm (11.9 inches)	91%	extreme
September Weather	24°C (76°F)	206 mm (8.1 inches)	84%	extreme
October Weather	19°C (67°F)	113 mm (4.5 inches)	83%	high
November Weather	13°C (56°F)	52 mm (2.1 inches)	81%	high
December Weather	8°C (46°F)	68 mm (2.7 inches)	79%	moderate