Satellite imagery shows dry air masses appear to originate over several regions of the African continent. Soundings from Sal Island off of the western coast of Africa have been used to examine the dry air in the Saharan Air Layer. In addition to this air mass, dry air also appears to originate over tropical regions in Africa. Soundings from several sites in northwest Africa are examined for similar dry air signals. The goal is to determine whether these dry air signals can originate from rainy regions in Africa, as well as over the desert regions where they are already known to form. The effects of seasonal variability on atmospheric moisture over these tropical regions are also examined.