Weather is probably a major factor when you plan your trip to Calhau, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually October and September with an average temp of 81°F, while the coldest months are July and June with an average of 80°F. The rainiest months in Calhau are April, March, February, and May, with each month seeing an average of 21 inches of rainfall.