Rainfall in Chad follows a gradient from north to south, with rainfall increasing as you travel south. Three primary climatic zones follow this rain gradient, with the northern part of Chad in the arid Saharan Desert, transitioning into the sub-tropical, semi-arid Sahel region in central Chad, and converting to tropical savannah in the south. Southern Chad experiences a rainy season between May-October with rainfall totals between 150-300 mm per month. Average annual temperatures are highest during this season, ranging between 27-29°C. Central Chad experiences a shorter rainy season that lasts from June-September and receives around 50-150 mm of rainfall per month. Seasonal temperatures vary considerably with temperatures ranging from 20-27°C in the winter and between 27-35°C in the summer. Northern Chad extends into the Sahara Desert and receives very little annual rainfall with seasonal temperature variations similar to that of the central region. The dry season lasts between November-March and very little to no precipitation falls during this season. 

Temperature

• Mean annual temperatures in Chad have increased by 0.7°C since 1960. The greatest rate of increase occurred in the wet season during the months of July-September at a rate of 0.36°C per decade. 
• The Sahel and West Africa have experienced increasing near surface temperatures over the past 50 years.

Precipitation

• No trend in mean annual rainfall has been determined since 1960. The period between 2000-2006 has seen abnormally high amounts of rainfall in the dry season, but no consistent trend has been detected.
• Meteorological station data in southern Chad indicate decreasing precipitation trends during the rainy season (May-October), over the period of 1951-2000.
• The Sahel experienced an overall decrease in rainfall during the 20th century, with a recent recovery of rainfall during the last 20 years of the century.

This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.