Taking into account the local weather in Saint-Marcellin can help you maximize your time at the pool during your trip. The hottest months are usually July and August with an average temp of 60°F, while the coldest months are January and February with an average of 19°F. The snowiest months in Saint-Marcellin are March, January, February, and November, with each month seeing an average of 14 inches of snowfall.