Weather is probably a major factor when you plan your trip to Cowansville, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually July and August, with an average temperature of 18°C, while the coldest months are January and February, with an average of -6°C. The snowiest months in Cowansville are January, December, March and February, with each month seeing an average of 31 cm of snowfall.