If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Brazzaville: The hottest months are usually September and August with an average temp of 79°F, while the coldest months are July and June with an average of 77°F. The rainiest months in Brazzaville are November, December, April, and October, with each month seeing an average of 8 inches of rainfall.