Why do different regions of Ethiopia receive different amounts of rainfall?

The variation in rainfall across Ethiopia is primarily driven by the country's complex topography and its location within tropical latitudes, which subjects it to different seasonal weather patterns.1

Ethiopia is divided into four distinct rainfall regimes based on these geographic and climatic factors:

• Southern Western Highlands: This region receives rain year-round, with annual precipitation reaching up to 80 inches (2,000 mm).1
• Eastern Highlands and Northern Western Highlands: These areas receive rainfall primarily during the summer months, with annual totals around 55 inches (1,400 mm).1
• Eastern Lowlands: This region experiences a bimodal rainfall pattern, receiving rain twice a year (April–May and October–November) with two intervening dry periods. Annual precipitation ranges from 20 to 40 inches (500 to 1,000 mm).1
• Denakil Plain: As the driest region in the country, it receives less than 20 inches (500 mm) of rain annually, and in some years, it may receive none at all.1

These patterns are influenced by the seasonal movement of the intertropical convergence zone (ITCZ), which brings moisture-laden air and convective rainfall as it shifts north and south with the Sun.123