January Weather in Kosai, Japan

Last updated: August 23, 2025

In Kosai, Japan, the average temperature in January hovers around 6°C (44°F), with a minimum dipping to -2°C (29°F) and a maximum reaching 17°C (63°F). Expect about 49 mm (1.9 in) of precipitation spread over 4 days, contributing to an average humidity of 82%. Stay prepared for a chill and a touch of moisture during this month!

January Temperature in Kosai

In January in Kosai, the average temperature is 6°C (44°F). Maximum temperatures can reach 17°C (63°F), while minimums can dip as low as -2°C (29°F). Be prepared for a range of temperatures and pack accordingly for your travels!

January Weather in Kosai: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Kosai, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Kosai, January typically has an average temperature of 6°C (44°F), with highs reaching up to 17°C (63°F) and lows dropping to around -2°C (29°F).

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

January Precipitation in Kosai

In Kosai in January, the total precipitation amount is 49 mm (1.9 in) spread over a duration of 4 days.

January Precipitation Trends in Kosai

The chart displays monthly precipitation patterns in Kosai, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Kosai, January typically receives around 49 mm (1.9 inches) of precipitation spread over approximately 4 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

January Humidity in Kosai

In Kosai in January humidity is 82%. With an average temperature of 6°C (44°F), this humidity feels like a damp chill that settles into your bones, making travel uncomfortable as every step feels heavy with moisture and the cool air seems to cling to your skin.

January Average Humidity in Kosai

This chart illustrates the average monthly humidity levels in Kosai, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Kosai is approximately 82%, offering insight into how humid the weather typically is during this month.

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

January UV Index in Kosai

In Kosai in January, 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 Kosai for better planning.

Maximum UV Index Levels in Kosai for January

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

Data source: Kosai January 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 January Weather in Kosai Compares to Other Months

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

This table compares monthly weather conditions in Kosai, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	6°C (44°F)	49 mm (1.9 inches)	82%	moderate
February Weather	7°C (45°F)	69 mm (2.7 inches)	79%	moderate
March Weather	12°C (53°F)	154 mm (6.1 inches)	74%	very high
April Weather	16°C (60°F)	160 mm (6.3 inches)	76%	very high
May Weather	20°C (69°F)	187 mm (7.4 inches)	83%	extreme
June Weather	23°C (74°F)	240 mm (9.4 inches)	87%	extreme
July Weather	27°C (81°F)	385 mm (15.2 inches)	93%	extreme
August Weather	29°C (85°F)	189 mm (7.4 inches)	91%	extreme
September Weather	25°C (78°F)	217 mm (8.5 inches)	87%	very high
October Weather	20°C (68°F)	284 mm (11.2 inches)	85%	high
November Weather	14°C (58°F)	75 mm (2.9 inches)	83%	moderate
December Weather	9°C (48°F)	65 mm (2.6 inches)	83%	moderate