If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Tepotzotlán: The hottest months are usually April and May with an average temp of 64°F, while the coldest months are January and December with an average of 57°F. The rainiest months in Tepotzotlán are August, July, September, and June, with each month seeing an average of 7 inches of rainfall.