January Weather in Washington, United States

Last updated: June 24, 2025

In January, the average temperature in Washington, United States hovers around -5°C (24°F), with a minimum dipping to -19°C (-1°F) and a maximum reaching 4°C (40°F). Expect around 44 mm (1.7 in) of precipitation spread over 8 days, contributing to the region's high average humidity of 91%. Stay prepared for a chilly month!

January Temperature in Washington

In January in Washington, the average temperature is -5°C (24°F), with maximums reaching 4°C (40°F) and minimums dropping as low as -19°C (-1°F). Travelers should be prepared for cold conditions and pack accordingly to fully enjoy their visit.

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

The chart illustrates January temperature patterns in Washington, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Washington, January typically has an average temperature of -5°C (24°F), with highs reaching up to 4°C (40°F) and lows dropping to around -19°C (-1°F).

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

January Precipitation in Washington

In Washington in January, the total precipitation amount is 44 mm (1.7 in) over a duration of 8 days.

January Precipitation Trends in Washington

The chart displays monthly precipitation patterns in Washington, 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 Washington, January typically receives around 44 mm (1.7 inches) of precipitation spread over approximately 8 days.

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

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Millimeters (mm) Inches (in)

January Humidity in Washington

In Washington in January humidity is 91%. With an average temperature of -5°C (24°F), this humidity makes the cold feel even more biting and penetrative, creating a chilling atmosphere that's quite uncomfortable for traveling.

January Average Humidity in Washington

This chart illustrates the average monthly humidity levels in Washington, 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 Washington is approximately 91%, 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 Washington

In Washington in January, 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 Washington, you can visit Hourly UV Index in Washington.

Maximum UV Index Levels in Washington for January

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

Data source: Washington 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 Washington Compares to Other Months

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

This table compares monthly weather conditions in Washington, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-5°C (24°F)	44 mm (1.7 inches)	91%	low
February Weather	-5°C (23°F)	56 mm (2.2 inches)	91%	moderate
March Weather	-1°C (30°F)	61 mm (2.4 inches)	87%	moderate
April Weather	2°C (36°F)	90 mm (3.5 inches)	87%	high
May Weather	7°C (45°F)	83 mm (3.3 inches)	82%	very high
June Weather	14°C (57°F)	90 mm (3.5 inches)	79%	very high
July Weather	20°C (68°F)	76 mm (3.0 inches)	75%	very high
August Weather	20°C (68°F)	87 mm (3.4 inches)	76%	very high
September Weather	17°C (62°F)	85 mm (3.4 inches)	79%	high
October Weather	11°C (51°F)	114 mm (4.5 inches)	83%	moderate
November Weather	3°C (38°F)	67 mm (2.6 inches)	86%	moderate
December Weather	-1°C (30°F)	70 mm (2.8 inches)	87%	low