Weather will likely play an important role when you plan your trip to Imperatriz, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually September and August with an average temp of 84°F, while the coldest months are July and June with an average of 79°F. The rainiest months in Imperatriz are March, February, January, and April, with each month seeing an average of 10 inches of rainfall.