If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Muonio: The hottest months are usually July and August with an average temp of 52°F, while the coldest months are January and February with an average of 14°F. The snowiest months in Muonio are March, January, February, and December, with each month seeing an average of 106 inches of snowfall.