Weather is probably a major factor when you plan your trip to Drumheller, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually August and July, with an average temperature of 15°C, while the coldest months are December and February, with an average of -7°C. The snowiest months in Drumheller are March, January, February and November, with each month seeing an average of 16 cm of snowfall.