January Weather in Eureka, United States

Last updated: June 24, 2025

In January, the average temperature in Eureka, United States hovers around 0°C (33°F). Expect a chilling minimum of -21°C (-5°F) and a comfortable maximum of 20°C (68°F). With an average precipitation of 75 mm (3.0 in) over 7 days, be prepared for some wet weather. The air carries a notable humidity of 82%, adding to the season's distinct feel.

January Temperature in Eureka

In January in Eureka, the average temperature is 0°C (33°F). Maximum temperatures can reach 20°C (68°F), while minimums can drop as low as -21°C (-5°F). Travelers should be prepared for a wide range of temperatures, ensuring they pack accordingly for both cold and mild weather.

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 0°C (33°F), with highs reaching up to 20°C (68°F) and lows dropping to around -21°C (-5°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 75 mm (3.0 in) over a span of 7 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 75 mm (3.0 inches) of precipitation spread over approximately 7 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 82%. With an average temperature of 0°C (33°F), this humidity feels like a damp chill that seeps into your bones, making outdoor adventures feel much colder than the mercury suggests, and reminding you to bundle up as you explore.

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 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 Eureka

In Eureka in January, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Eureka, you can check the information here.

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 3, 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	0°C (33°F)	75 mm (3.0 inches)	82%	moderate
February Weather	2°C (36°F)	81 mm (3.2 inches)	80%	moderate
March Weather	8°C (47°F)	129 mm (5.1 inches)	80%	high
April Weather	13°C (55°F)	124 mm (4.9 inches)	80%	very high
May Weather	19°C (67°F)	144 mm (5.7 inches)	82%	very high
June Weather	24°C (76°F)	88 mm (3.5 inches)	83%	extreme
July Weather	26°C (80°F)	95 mm (3.7 inches)	81%	very high
August Weather	24°C (76°F)	139 mm (5.5 inches)	80%	very high
September Weather	22°C (72°F)	56 mm (2.2 inches)	76%	very high
October Weather	15°C (59°F)	110 mm (4.3 inches)	76%	high
November Weather	7°C (45°F)	70 mm (2.8 inches)	85%	moderate
December Weather	4°C (40°F)	57 mm (2.2 inches)	86%	moderate