Several summer (JJA) and winter (DJF) seasons of 2A25 Tropical Rainfall Measuring Mission Precipitation Radar (TRMM PR) data are used to study the spatial and diurnal variability of precipitation, and the vertical profile of precipitation systems, over Africa. This continent is divided into several climatologically rather homogenous regions, and those regions are characterized and contrasted. A preliminary assessment, based on just one month of data, reveals a bi-modal pattern in the diurnal cycle of surface rain rate and reflectivity for the Sahel and Ethiopian highland regions. A very clear afternoon peak on convective activity occurs between 1800-2100 LT and a morning peak occurs between 0900-1200 LT in both these regions. On the other hand, there is a single afternoon maximum over most desert regions such as the Sahara. Frequency-by-altitude diagrams indicate that strong low-level reflectivities are more common in the Sahel region compared with the other regions in the northern part of Africa.