Weather is probably a major factor when you plan your trip to Ca Mau, and keep in mind that cheaper options are usually available when the weather isn’t as good. The hottest months are usually April and March with an average temp of 84°F, while the coldest months are January and December with an average of 80°F. The rainiest months in Ca Mau are October, September, July, and June, with each month seeing an average of 14 inches of rainfall.