Dodoma sits on the dry central plateau and has a semi-arid climate — much drier and more temperate than the humid coast. There are two short rainy seasons, the heavier one from November to April and a lighter pattern of showers afterwards, but the rains are unreliable and total rainfall is modest.
The most pleasant time to visit is the long dry season from May to October, when days are warm but rarely hot and nights can be genuinely cool. December and January are hot. The town is at its liveliest when parliament is in session — usually for a few weeks in February, June, and November — when hotels fill up and prices rise. If you want a quiet visit, come outside those windows.