December Weather in Westminster, United States

Last updated: June 24, 2025

In December, the average temperature in Westminster, United States hovers around 4°C (39°F), with potential dips to a chilly -12°C (10°F) and peaks reaching up to a pleasant 18°C (65°F). Expect 96 mm (3.8 in) of precipitation spread over approximately 9 days, and prepare for a high average humidity of 84%. Stay bundled up and ready for the dampness!

December Temperature in Westminster

In December in Westminster, the average temperature is 4°C (39°F). The maximum can reach 18°C (65°F), while the minimum can plunge as low as -12°C (10°F). Be sure to dress in layers and prepare for a mix of chilly and mild weather if you plan to visit during this time.

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

The chart illustrates December temperature patterns in Westminster, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Westminster, December typically has an average temperature of 4°C (39°F), with highs reaching up to 18°C (65°F) and lows dropping to around -12°C (10°F).

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

December Precipitation in Westminster

In Westminster in December, the total precipitation amount is 96 mm (3.8 in) spread over a period of 9 days.

December Precipitation Trends in Westminster

The chart displays monthly precipitation patterns in Westminster, 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 Westminster, December typically receives around 96 mm (3.8 inches) of precipitation spread over approximately 9 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

December Humidity in Westminster

In Westminster in December, humidity is 84%. With an average temperature of 4°C (39°F), this humidity feels like a damp chill that seeps into your bones, making outdoor excursions uncomfortable and demanding more layers than you anticipate while traveling.

December Average Humidity in Westminster

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

In Westminster in December, 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 Westminster, you can check the information here.

Maximum UV Index Levels in Westminster for December

The chart shows the monthly maximum UV Index (UVI) for Westminster 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 Westminster typically reaches 3, which falls under the moderate exposure category.

Data source: Westminster 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 Westminster Compares to Other Months

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

This table compares monthly weather conditions in Westminster, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	2°C (35°F)	62 mm (2.4 inches)	84%	moderate
February Weather	4°C (39°F)	95 mm (3.8 inches)	83%	moderate
March Weather	7°C (44°F)	93 mm (3.6 inches)	83%	high
April Weather	12°C (55°F)	95 mm (3.7 inches)	81%	very high
May Weather	18°C (64°F)	144 mm (5.7 inches)	78%	very high
June Weather	23°C (73°F)	125 mm (4.9 inches)	79%	very high
July Weather	26°C (78°F)	152 mm (6.0 inches)	74%	very high
August Weather	24°C (76°F)	156 mm (6.1 inches)	72%	very high
September Weather	21°C (70°F)	116 mm (4.5 inches)	75%	very high
October Weather	15°C (60°F)	103 mm (4.1 inches)	81%	high
November Weather	7°C (45°F)	90 mm (3.6 inches)	85%	moderate
December Weather	4°C (39°F)	96 mm (3.8 inches)	84%	moderate