December Weather in Harriston, Canada

Last updated: June 18, 2025

In December, the average temperature in Harriston, Canada hovers around -3°C (28°F), with a notable range from a chilling -26°C (-15°F) to a milder 16°C (60°F). Expect about 83 mm (3.2 in) of precipitation over 17 days, contributing to an average humidity level of 87%. Be prepared for a truly wintry experience!

December Temperature in Harriston

In December in Harriston, the average temperature is -3°C (28°F), with maximums reaching up to 16°C (60°F) and minimums plunging as low as -26°C (-15°F). It's essential to pack warm clothing and prepare for a range of weather conditions if you're planning to travel during this time.

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

The chart illustrates December temperature patterns in Harriston, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Harriston, December typically has an average temperature of -3°C (28°F), with highs reaching up to 16°C (60°F) and lows dropping to around -26°C (-15°F).

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

December Precipitation in Harriston

In Harriston in December, the total precipitation amount is 83 mm (3.2 in) spread over 17 days.

December Precipitation Trends in Harriston

The chart displays monthly precipitation patterns in Harriston, 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 Harriston, December typically receives around 83 mm (3.2 inches) of precipitation spread over approximately 17 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 Harriston

In Harriston in December humidity is 87%. With an average temperature of -3°C (28°F), this humidity feels like a biting chill that clings to your skin, making travel quite uncomfortable and forcing you to bundle up extra just to stay warm.

December Average Humidity in Harriston

This chart illustrates the average monthly humidity levels in Harriston, 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 Harriston is approximately 87%, 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 Harriston

In Harriston 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 Harriston, you can visit Hourly UV Index in Harriston.

Maximum UV Index Levels in Harriston for December

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

Data source: Harriston 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 Harriston Compares to Other Months

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

This table compares monthly weather conditions in Harriston, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-6°C (21°F)	76 mm (3.0 inches)	90%	low
February Weather	-6°C (22°F)	83 mm (3.3 inches)	90%	moderate
March Weather	-1°C (30°F)	70 mm (2.8 inches)	87%	moderate
April Weather	5°C (41°F)	107 mm (4.2 inches)	87%	very high
May Weather	12°C (54°F)	103 mm (4.1 inches)	82%	very high
June Weather	18°C (64°F)	106 mm (4.2 inches)	81%	very high
July Weather	20°C (69°F)	89 mm (3.5 inches)	79%	very high
August Weather	19°C (67°F)	110 mm (4.3 inches)	80%	very high
September Weather	15°C (60°F)	94 mm (3.7 inches)	81%	high
October Weather	9°C (49°F)	111 mm (4.4 inches)	84%	moderate
November Weather	1°C (35°F)	95 mm (3.8 inches)	88%	moderate
December Weather	-3°C (28°F)	83 mm (3.2 inches)	87%	low