If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Thayerville: The hottest months are usually July and August with an average temp of 66°F, while the coldest months are January and February with an average of 32°F. The snowiest months in Thayerville are January, December, February, and May, with each month seeing an average of 31 inches of snowfall.