December Weather in Sion, Canada

Last updated: June 18, 2025

In Sion, Canada, the average temperature in December hovers around -4°C (26°F), with extremes ranging from a chilly -28°C (-18°F) to a milder 12°C (53°F). Be prepared for approximately 72 mm (2.8 in) of precipitation over 14 days, contributing to an average humidity level of 93%. Bundle up and enjoy the wintry atmosphere!

December Temperature in Sion

In December in Sion, the average temperature is -4°C (26°F), with maximums reaching up to 12°C (53°F) and minimums plummeting as low as -28°C (-18°F). It's essential to pack warm clothing if you plan to travel during this month, as temperatures can vary significantly.

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

The chart illustrates December temperature patterns in Sion, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Sion, December typically has an average temperature of -4°C (26°F), with highs reaching up to 12°C (53°F) and lows dropping to around -28°C (-18°F).

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

December Precipitation in Sion

In Sion in December, the total precipitation amount is 72 mm (2.8 in) spread over the course of 14 days.

December Precipitation Trends in Sion

The chart displays monthly precipitation patterns in Sion, 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 Sion, December typically receives around 72 mm (2.8 inches) of precipitation spread over approximately 14 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 Sion

In Sion in December, humidity is 93%. With an average temperature of -4°C (26°F), this humidity feels like a heavy chill that seeps into your bones, making traveling uncomfortable and requiring extra layers to stay warm and dry.

December Average Humidity in Sion

This chart illustrates the average monthly humidity levels in Sion, 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 Sion is approximately 93%, 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 Sion

In Sion in December, the maximum UV index is 1, which corresponds to a low Exposure Category. This means you have a time to burn of 45 minutes. For more details, you can check the Hourly UV Index in Sion.

Maximum UV Index Levels in Sion for December

The chart shows the monthly maximum UV Index (UVI) for Sion 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 Sion typically reaches 1, which falls under the low exposure category.

Data source: Sion 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 Sion Compares to Other Months

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

This table compares monthly weather conditions in Sion, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-5°C (24°F)	74 mm (2.9 inches)	90%	low
February Weather	-5°C (24°F)	59 mm (2.3 inches)	91%	moderate
March Weather	1°C (34°F)	68 mm (2.7 inches)	89%	moderate
April Weather	5°C (42°F)	69 mm (2.7 inches)	85%	high
May Weather	12°C (53°F)	66 mm (2.6 inches)	82%	very high
June Weather	16°C (61°F)	45 mm (1.8 inches)	81%	very high
July Weather	20°C (69°F)	13 mm (0.5 inches)	84%	very high
August Weather	20°C (68°F)	18 mm (0.7 inches)	75%	very high
September Weather	13°C (57°F)	45 mm (1.8 inches)	74%	high
October Weather	5°C (42°F)	59 mm (2.3 inches)	85%	moderate
November Weather	0°C (33°F)	71 mm (2.8 inches)	88%	low
December Weather	-4°C (26°F)	72 mm (2.8 inches)	93%	low