Country music is not the MidWest and Memphis and Nashville are South. Saint Louis is a bit of a border city. It can feel Midwestern, but can also feel Southern at times. Most people I've talked to in Saint Louis call it the MidWest and given its place in American history it makes a lot of sense. Again, terms like MidWest always blur a bit on the edges and Saint Louis is a good example. Architecturally it's got a lot of Southern French influence. Music-wise it's mainly blues and the home of Chuck Berry.
The similarities in MidWest that I see in Winnipeg are mainly as a transportation hub opening up the further west portions of Canada. As well, Winnipeg's great stock of turn of the century warehouse buildings immediately gives a Chicago feel.
As arnold said, Midwestern is just wrong for Canada. Midwestern is a US thing, Prairie is a Canada thing. Bring back Prairie with Alberta included. Especially given the number of people in Alberta that called Saskatchewan home it's good to see it all in one spot. Or at least convenient for me having lived in all three Prairie provinces in my life.