January Weather in Eureka, United States

Last updated: June 24, 2025

In Eureka, United States, the average temperature in January hovers around -4°C (25°F), with a notable range where it can dip as low as -26°C (-14°F) and peak at 16°C (61°F). Expect a total precipitation of 29 mm (1.1 in) spread over 6 days, and prepare for an average humidity of 84%.

January Temperature in Eureka

In January in Eureka, the average temperature is -4°C (25°F). The maximum can reach 16°C (61°F), while the minimum can drop as low as -26°C (-14°F). It's advisable to dress warmly and be prepared for a wide range of temperatures if you plan to visit during this time.

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

The chart illustrates January temperature patterns in Eureka, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Eureka, January typically has an average temperature of -4°C (25°F), with highs reaching up to 16°C (61°F) and lows dropping to around -26°C (-14°F).

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

January Precipitation in Eureka

In Eureka in January, the precipitation amount is 29 mm (1.1 in) over the course of 6 days.

January Precipitation Trends in Eureka

The chart displays monthly precipitation patterns in Eureka, 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 Eureka, January typically receives around 29 mm (1.1 inches) of precipitation spread over approximately 6 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 Eureka

In Eureka in January, humidity is 84%. With an average temperature of -4°C (25°F), this humidity feels like a biting chill that seeps into your bones, making outdoor activities uncomfortable and travel less enjoyable.

January Average Humidity in Eureka

This chart illustrates the average monthly humidity levels in Eureka, 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 Eureka is approximately 84%, 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 Eureka

In Eureka 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 Eureka for better planning.

Maximum UV Index Levels in Eureka for January

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

Data source: Eureka 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 Eureka Compares to Other Months

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

This table compares monthly weather conditions in Eureka, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (25°F)	29 mm (1.1 inches)	84%	moderate
February Weather	-3°C (27°F)	29 mm (1.1 inches)	87%	high
March Weather	1°C (35°F)	57 mm (2.3 inches)	80%	very high
April Weather	8°C (46°F)	39 mm (1.5 inches)	71%	very high
May Weather	12°C (55°F)	39 mm (1.5 inches)	55%	extreme
June Weather	20°C (68°F)	10 mm (0.4 inches)	51%	extreme
July Weather	25°C (77°F)	16 mm (0.6 inches)	41%	extreme
August Weather	24°C (75°F)	9 mm (0.3 inches)	32%	extreme
September Weather	18°C (65°F)	12 mm (0.5 inches)	41%	very high
October Weather	9°C (48°F)	22 mm (0.9 inches)	61%	high
November Weather	4°C (39°F)	22 mm (0.8 inches)	79%	moderate
December Weather	-3°C (26°F)	29 mm (1.1 inches)	83%	moderate