Taking into account the local weather in Saint-Louis-du-Ha! Ha! is an important factor for planning your visit, especially if you plan to spend your trip poolside. The hottest months are usually July and August with an average temp of 61°F, while the coldest months are January and February with an average of 17°F. The snowiest months in Saint-Louis-du-Ha! Ha! are March, January, February, and December, with each month seeing an average of 14 inches of snowfall.