December Weather in Isawa, Japan

Last updated: August 23, 2025

In December, the average temperature in Isawa, Japan hovers around 2°C (36°F), offering a chill that can drop to a brisk -8°C (17°F). However, you might experience milder days with a maximum of 18°C (65°F). Be prepared for some rain, as 52 mm (2.1 in) of precipitation is expected over 8 days, contributing to an average humidity of 78%. Dress warmly and enjoy the dynamic weather!

December Temperature in Isawa

In December in Isawa, the average temperature is 2°C (36°F). Maximums can reach 18°C (65°F) and minimums can be as low as -8°C (17°F). It's a perfect time for travelers to layer up and enjoy the crisp, cool weather while exploring the area's winter activities.

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

The chart illustrates December temperature patterns in Isawa, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Isawa, December typically has an average temperature of 2°C (36°F), with highs reaching up to 18°C (65°F) and lows dropping to around -8°C (17°F).

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

December Precipitation in Isawa

In Isawa in December, the total precipitation amount is 52 mm (2.1 in) over the course of 8 days.

December Precipitation Trends in Isawa

The chart displays monthly precipitation patterns in Isawa, 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 Isawa, December typically receives around 52 mm (2.1 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 Isawa

In Isawa in December, humidity is 78%. With an average temperature of 2°C (36°F), this humidity feels like a biting chill that seeps into your bones, making outdoor travel uncomfortable and necessitating heavy layers to stay warm while navigating the damp air.

December Average Humidity in Isawa

This chart illustrates the average monthly humidity levels in Isawa, 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 Isawa is approximately 78%, 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 Isawa

In Isawa 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 Isawa for better planning.

Maximum UV Index Levels in Isawa for December

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

Data source: Isawa 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 Isawa Compares to Other Months

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

This table compares monthly weather conditions in Isawa, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-1°C (31°F)	48 mm (1.9 inches)	76%	moderate
February Weather	0°C (33°F)	58 mm (2.3 inches)	74%	high
March Weather	5°C (41°F)	144 mm (5.7 inches)	70%	very high
April Weather	9°C (48°F)	138 mm (5.4 inches)	74%	very high
May Weather	14°C (58°F)	148 mm (5.8 inches)	81%	extreme
June Weather	17°C (63°F)	179 mm (7.1 inches)	88%	extreme
July Weather	21°C (70°F)	320 mm (12.6 inches)	93%	extreme
August Weather	23°C (73°F)	190 mm (7.5 inches)	90%	extreme
September Weather	18°C (65°F)	208 mm (8.2 inches)	86%	very high
October Weather	13°C (55°F)	324 mm (12.8 inches)	83%	high
November Weather	7°C (45°F)	56 mm (2.2 inches)	80%	moderate
December Weather	2°C (36°F)	52 mm (2.1 inches)	78%	moderate