Weather is only one factor, but it can really affect your travel plans, especially if you are planning a longer stay in Morristown. The hottest months are usually July and August, with an average temperature of 21°C, while the coldest months are January and February, with an average of -5°C. The snowiest months in Morristown are March, January, October and April, with each month seeing an average of 15 cm of snowfall.