Quote from BC Gildenhuys on June 1, 2022, 6:12 pm

South Africa's well-being cannot be separated from rainfall. Good rainfall gives good agricultural years which is good for our economy, and may we say our county's mood. Today's map shows two significant aspects of rainfall. Firstly, by all definitions, South Africa is an arid country with the more substantial portion getting less than 400mm per annum. It is clear how our topography impacts rainfall, but rainfall determines agricultural activities and proves to be an essential determinant in human settlement. We will highlight this in subsequent posts. Watch the 400mm isohyet. It might be one of the most defining lines in South Africa's economy and society. 

https://sdsafrica.net/where-does-it-rain/