"The Pittsburgh accent actually sounds (very slightly) southern."
I've always considered PA to be a midwestern state, whether it technically is or not. Maybe that is the accent I notice in the state.
I don't know about the Pittsburgh accent, but my sophomore year in college at James Madison University in Harrisonburg, VA (up in the Shenendoah Valley), we had a guy on my hall from somewhere around Happy Valley, PA. His Appalachian drawl was so thick, you'd think he was from down in the Virginia/Kentucky coal country, but he was born and raised up around Happy Valley. I have no idea where that accent came from.
Fascinating place, Pennsylvania. I had friends from all over PA in college and a few years afterward living in DC. Great folks, mostly, except for the two hardcore bodybuilding third-generation Polish-American racists from Johnstown that I roomed with for half a year. Those guys' attitudes and vocabularies about anybody non-white would've made an Alabama Klansman blanch.
}:-)4
Nope. The midwest starts one mile west of Zanesville, Ohio. All of Ohio east of there and Western Pennsylvania is Appalachia. Big time.