It seems that the balding men in my family (two maternal uncles) bald in a similar way. On is NW3, one is NW3.5 both with vertex thinning. This also seems to follow their maternal grandfather who I never met, but in old age still retained central forelock. Currently my balding pattern looks somewhere between both uncles.
I'm hoping that I'll at least follow the familial pattern and still keep some sort of hair in the middle, but yesterday I found a pic of my great, great grandfather (maternal side) who has the nw7 pattern (although only pic is him as an old man) so now I'm not sure where I'll end up.