December Weather in Thief River Falls, United States

Last updated: June 24, 2025

In Thief River Falls, United States, the average temperature in December hovers around -9°C (16°F), but it can plummet to a chilling -36°C (-32°F) or rise to a maximum of 7°C (45°F). During this month, you can expect 38 mm (1.5 in) of precipitation spread over approximately 8 days, with the air feeling quite moist at an average humidity of 86%.

December Temperature in Thief River Falls

In December in Thief River Falls, the average temperature is -9°C (16°F). The maximum can reach 7°C (45°F) and the minimum can be as low as -36°C (-32°F). Travelers should be prepared for extreme cold conditions and dress in layers to stay warm during this time.

December Weather in Thief River Falls: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Thief River Falls, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Thief River Falls, December typically has an average temperature of -9°C (16°F), with highs reaching up to 7°C (45°F) and lows dropping to around -36°C (-32°F).

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

December Precipitation in Thief River Falls

In Thief River Falls in December, the total precipitation amount is 38 mm (1.5 in), spread over 8 days.

December Precipitation Trends in Thief River Falls

The chart displays monthly precipitation patterns in Thief River Falls, 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 Thief River Falls, December typically receives around 38 mm (1.5 inches) of precipitation spread over approximately 8 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 Thief River Falls

In Thief River Falls in December, humidity is 86%. With an average temperature of -9°C (16°F), this humidity feels like a cold, biting chill that seeps into your bones, making outdoor activities less enjoyable and travel quite uncomfortable.

December Average Humidity in Thief River Falls

This chart illustrates the average monthly humidity levels in Thief River Falls, 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 Thief River Falls is approximately 86%, 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 Thief River Falls

In Thief River Falls 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 Thief River Falls, you can visit Hourly UV Index in Thief River Falls.

Maximum UV Index Levels in Thief River Falls for December

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

Data source: Thief River Falls 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 Thief River Falls Compares to Other Months

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

This table compares monthly weather conditions in Thief River Falls, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-13°C (9°F)	19 mm (0.8 inches)	90%	low
February Weather	-14°C (8°F)	22 mm (0.9 inches)	92%	moderate
March Weather	-3°C (27°F)	26 mm (1.0 inches)	85%	moderate
April Weather	3°C (39°F)	43 mm (1.7 inches)	81%	high
May Weather	13°C (55°F)	54 mm (2.1 inches)	75%	very high
June Weather	20°C (68°F)	93 mm (3.7 inches)	79%	very high
July Weather	22°C (71°F)	62 mm (2.4 inches)	76%	very high
August Weather	20°C (68°F)	69 mm (2.7 inches)	78%	very high
September Weather	15°C (59°F)	84 mm (3.3 inches)	77%	high
October Weather	6°C (43°F)	81 mm (3.2 inches)	79%	moderate
November Weather	-3°C (26°F)	29 mm (1.1 inches)	86%	low
December Weather	-9°C (16°F)	38 mm (1.5 inches)	86%	low