That is why Somalia is not bone dry like the Sahara. It is semi-arid. It gets some rain from the Indian Ocean. The crucial extra rain from the West is blocked by the Ethiopian highlands. Otherwise, it would have been a green country.
Go to Google Earth and compare the highland Tigray-Amhara region of Ethiopia to the lowland Afar region.
The Ethiopian highlands make North-Central Somalia dry.
If this was the case then Galbeed would be bereft of green lands, dire dawa and its environs would be dry.
Furthermore the Ethiopian Highlands are a collective of mountain ranges. Not one long continuous mountain range.
To explain Somalia's issue of aridity with the mountains isnt reasonable, because what reason would there be for Sudan? Egypt? The Sahara?
The causes of Somalias rainfall issue could at best be minimally explained by the Ethiopian Highlands