Caseless:
do you have equal rainfall distribution in the south? What's the depth of rainfall(mm) in the south? Rainfall increases from south to north, I know. But don't lump everything together...even in the south, you have variations. This is what I want you to point out.

rainfall in akwaibom,bayelsa,rivers,southern delta,cross river axis has the highest mm of annual rainfall followed by Imo,abia,Lagos,southern ondo and Edo then you get the anambra,Enugu,ebonyi,northern delta,northern ondo and Edo before you now get to sw in general....no northern state whether central,west or east has the same annual rainfall with anywhere in the east