While there may be some inconsistency to these, the nomenclature that makes no sense geographically is Midwestern (divided into upper and lower) -- at the extreme we have Ohio and Indiana as Midwestern states. I suppose there is a historical explanation, but the map tells me they are "mideastern".

It may be that the Pacific Northwest is so named to prevent confusion with the Northwest Territories. As to the Western Seaboard, that would be California. :-)