January Weather in Cornwall, Canada

Last updated: June 18, 2025

In January, the average temperature in Cornwall, Canada hovers around -7°C (20°F). Temperatures can dip as low as -30°C (-22°F), while reaching a maximum of 14°C (57°F). Expect 85 mm (3.3 in) of precipitation spread over 11 days, coupled with a high average humidity of 93%. Stay warm and prepared for a chilly, wet month ahead!

January Temperature in Cornwall

In January in Cornwall, the average temperature is -7°C (20°F). Maximums can reach 14°C (57°F), while minimums can drop as low as -30°C (-22°F). Travelers should be prepared for a wide range of temperatures, ensuring they pack suitable clothing for both warm and extremely cold conditions.

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

The chart illustrates January temperature patterns in Cornwall, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Cornwall, January typically has an average temperature of -7°C (20°F), with highs reaching up to 14°C (57°F) and lows dropping to around -30°C (-22°F).

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

January Precipitation in Cornwall

In Cornwall in January, the total precipitation amount is 85 mm (3.3 in) over a span of 11 days.

January Precipitation Trends in Cornwall

The chart displays monthly precipitation patterns in Cornwall, 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 Cornwall, January typically receives around 85 mm (3.3 inches) of precipitation spread over approximately 11 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

January Humidity in Cornwall

In Cornwall in January, humidity is 93%. With an average temperature of -7°C (20°F), this humidity feels like a biting chill that cuts through your layers, making every outdoor adventure feel significantly harsher and requiring extra preparation for comfort during your travels.

January Average Humidity in Cornwall

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

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

Maximum UV Index Levels in Cornwall for January

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

Data source: Cornwall 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 Cornwall Compares to Other Months

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

This table compares monthly weather conditions in Cornwall, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-7°C (20°F)	85 mm (3.3 inches)	93%	low
February Weather	-6°C (22°F)	83 mm (3.3 inches)	92%	moderate
March Weather	-1°C (30°F)	87 mm (3.4 inches)	86%	moderate
April Weather	6°C (44°F)	117 mm (4.6 inches)	85%	very high
May Weather	14°C (57°F)	109 mm (4.3 inches)	80%	very high
June Weather	19°C (66°F)	100 mm (3.9 inches)	74%	very high
July Weather	22°C (72°F)	116 mm (4.6 inches)	76%	very high
August Weather	21°C (70°F)	100 mm (3.9 inches)	75%	very high
September Weather	16°C (62°F)	70 mm (2.8 inches)	78%	high
October Weather	10°C (51°F)	139 mm (5.5 inches)	86%	moderate
November Weather	2°C (36°F)	108 mm (4.2 inches)	88%	moderate
December Weather	-3°C (26°F)	84 mm (3.3 inches)	89%	low