If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Macungie: The hottest months are usually July and August with an average temp of 71°F, while the coldest months are January and February with an average of 34°F. The snowiest months in Macungie are February, January, December, and March, with each month seeing an average of 7 inches of snowfall.