Chad is located in central northern Africa at 7‐23° north of the equator, straddling the sub‐tropical climate band called the Sahel.
The north of Chad extends well into the arid Sahara desert, whilst the south has a much wetter, and typically tropical, climate. The northern, desert regions of Chad receive very little rainfall all year round. The southern, tropical savannah regions of Chad experience a wet season between May and October (receiving 150‐ 300mm per month), whilst the central sub‐tropical regions have a shorter wet season between June and September (receiving 50‐150 mm per month). In the dry months between November and March, almost no rain falls at all.
These seasonal rainfalls are controlled by the movement of the tropical rain belt (also known as the Inter‐Tropical Conversion Zone, ITCZ) which oscillates between the northern and southern tropics over the course of a year. Variations in the latitudinal movements of the ITCZ from one year to another cause large inter‐annual and decadal variability in wet‐season rainfall.
Source: University of Oxford, School of Geography and the Environment. Accessed on 23 November 2009 at: http://country-profiles.geog.ox.ac.uk/