Weather is probably a major factor when you plan your trip to Clark Fork, 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 18°C, while the coldest months are February and January, with an average of -2°C. The snowiest months in Clark Fork are January, February, December and March, with each month seeing an average of 43 cm of snowfall.