You might spend a lot of your vacation inside, but if you want to see more of the area, taking a look at local weather data can help you. The hottest months are usually May and June with an average temp of 82°F, while the coldest months are January and December with an average of 68°F. The rainiest months in Tamasopo are September, July, June, and August, with each month seeing an average of 8 inches of rainfall.