Garissa has a hot arid climate (Köppen climate classification BWh), despite receiving around  of rainfall per year, due to the extremely high potential evapotranspiration. Garissa's landscape is mostly arid, desert terrain.
Garissa has a scorching desert climate (Köppen climate classification BWh), despite receiving relatively little rainfall annually, due to the exceptionally high potential evapotranspiration. Garissa's landscape is predominantly arid and desert-like terrain.