January Weather in Sarnia, Canada

Last updated: June 18, 2025

In January, the average temperature in Sarnia, Canada hovers around -3°C (27°F), with extremes ranging from a chilling -23°C (-10°F) to a milder 10°C (51°F). Expect about 60 mm (2.4 in) of precipitation spread over 8 days, while the average humidity settles at a high 88%. Prepare for a cool, damp month that adds a distinct charm to the region!

January Temperature in Sarnia

In January in Sarnia, the average temperature is -3°C (27°F). The maximum can reach 10°C (51°F), while the minimum can drop as low as -23°C (-10°F). Travelers should prepare for chilly weather and varying conditions, making warm clothing essential for their visit.

January Weather in Sarnia: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Sarnia, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Sarnia, January typically has an average temperature of -3°C (27°F), with highs reaching up to 10°C (51°F) and lows dropping to around -23°C (-10°F).

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

January Precipitation in Sarnia

In Sarnia in January, the total precipitation amount is 60 mm (2.4 in) spread over the course of 8 days.

January Precipitation Trends in Sarnia

The chart displays monthly precipitation patterns in Sarnia, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Sarnia, January typically receives around 60 mm (2.4 inches) of precipitation spread over approximately 8 days.

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

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Millimeters (mm) Inches (in)

January Humidity in Sarnia

In Sarnia in January humidity is 88%. With an average temperature of -3°C (27°F), this humidity feels like a biting chill that seeps into your bones, making outdoor exploration less inviting as the dampness clings to your clothing and slows your movements.

January Average Humidity in Sarnia

This chart illustrates the average monthly humidity levels in Sarnia, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Sarnia is approximately 88%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Sarnia

In Sarnia in January, 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 Sarnia, you can visit Hourly UV Index in Sarnia.

Maximum UV Index Levels in Sarnia for January

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

Data source: Sarnia January 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 January Weather in Sarnia Compares to Other Months

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

This table compares monthly weather conditions in Sarnia, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-3°C (27°F)	60 mm (2.4 inches)	88%	low
February Weather	-3°C (28°F)	66 mm (2.6 inches)	87%	moderate
March Weather	1°C (35°F)	63 mm (2.5 inches)	85%	moderate
April Weather	7°C (45°F)	95 mm (3.7 inches)	86%	very high
May Weather	13°C (57°F)	97 mm (3.8 inches)	80%	very high
June Weather	20°C (68°F)	86 mm (3.4 inches)	80%	very high
July Weather	23°C (73°F)	73 mm (2.9 inches)	80%	very high
August Weather	22°C (72°F)	79 mm (3.1 inches)	80%	very high
September Weather	18°C (65°F)	73 mm (2.9 inches)	80%	high
October Weather	12°C (54°F)	106 mm (4.2 inches)	84%	moderate
November Weather	4°C (40°F)	72 mm (2.8 inches)	89%	moderate
December Weather	0°C (33°F)	55 mm (2.2 inches)	86%	low