Weather is probably a major factor when you plan your trip to Tarma, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually November and October with an average temp of 49°F, while the coldest months are July and August with an average of 46°F. The rainiest months in Tarma are February, January, December, and March, with each month seeing an average of 14 inches of rainfall.