Relative humidity is low, and the potential evaporation is greater than precipitation. As mentioned above, rains are infrequent, but occur in the winter during strong storm activity. Also during the winter months, the region is susceptible to cyclones, which travel from the Mediterranean through this region to India. ENSO events figure into the prevailing global conditions that make the Middle East so arid. The West Coast of Africa where Nigeria located received highest precipitation in this continent, up to more than 100 inches per year.
Precipitation decreases with latitude as one approach the dry belt of the two hemisphere.
Plateau of Algeria. Despite of low altitude, the relatively high elevation ensures a relatively mild and dry climate. Because of Atlas Mountain, the winter rain, which accompanied with migratory cyclones, are prevented from invading Southern Algeria. However, some cyclones center cross Algeria and bring some winter rainfall. Quasi-stationary summer front sometimes located across Algeria.