Taking the local weather in Monson into account is an important factor for planning your visit, especially if you plan to spend your trip by the pool. 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 Monson are March, January, April and December, with each month seeing an average of 56 cm of snowfall.