Weather will likely play an important role when you plan your trip to Sils-Maria, 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 10°C, while the coldest months are January and February, with an average of -7°C. The snowiest months in Sils-Maria are March, February, May and January, with each month seeing an average of 273 cm of snowfall.