December Weather in Eureka, United States

Last updated: June 24, 2025

In December, the average temperature in Eureka, United States hovers around -6°C (22°F), with a minimum drop as low as -28°C (-17°F) and a maximum reaching 15°C (60°F). This chilly month brings about 27 mm (1.1 in) of precipitation over 5 days, while the average humidity lingers at a brisk 81%. Embrace the crisp air and prepare for winter's touch!

December Temperature in Eureka

In December in Eureka, the average temperature is -6°C (22°F). Maximums can reach 15°C (60°F) and minimums can be as low as -28°C (-17°F). Travelers should be prepared for a wide range of temperatures and pack accordingly for both cold and mild conditions.

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

The chart illustrates December 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, December typically has an average temperature of -6°C (22°F), with highs reaching up to 15°C (60°F) and lows dropping to around -28°C (-17°F).

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

December Precipitation in Eureka

In Eureka in December, the precipitation amount is 27 mm (1.1 in) over a period of 5 days.

December Precipitation Trends in Eureka

The chart displays monthly precipitation patterns in Eureka, 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 Eureka, December typically receives around 27 mm (1.1 inches) of precipitation spread over approximately 5 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 Eureka

In Eureka in December, humidity is 81%. With an average temperature of -6°C (22°F), this humidity feels like a biting chill that penetrates layers of clothing, making travel uncomfortable and the air heavy with frost.

December Average Humidity in Eureka

This chart illustrates the average monthly humidity levels in Eureka, 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 Eureka is approximately 81%, 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 Eureka

In Eureka in December, 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 Eureka, you can visit Hourly UV Index in Eureka.

Maximum UV Index Levels in Eureka for December

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

Data source: Eureka 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 Eureka Compares to Other Months

Weather in Eureka varies notably across the year, with each month offering distinct climate conditions. This page compares December’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 December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-10°C (15°F)	14 mm (0.6 inches)	81%	low
February Weather	-11°C (13°F)	17 mm (0.7 inches)	85%	moderate
March Weather	-1°C (30°F)	29 mm (1.1 inches)	76%	moderate
April Weather	4°C (40°F)	43 mm (1.7 inches)	79%	high
May Weather	13°C (56°F)	57 mm (2.2 inches)	76%	very high
June Weather	21°C (70°F)	59 mm (2.3 inches)	81%	very high
July Weather	23°C (74°F)	63 mm (2.5 inches)	82%	very high
August Weather	21°C (70°F)	102 mm (4.0 inches)	82%	very high
September Weather	16°C (62°F)	69 mm (2.7 inches)	77%	very high
October Weather	7°C (44°F)	63 mm (2.5 inches)	76%	moderate
November Weather	0°C (32°F)	14 mm (0.5 inches)	84%	moderate
December Weather	-6°C (22°F)	27 mm (1.1 inches)	81%	low