The dude abides.
Back in I think the late 60’s in a history/culture class, our teacher said our area of the country around the Grate Lakes was the only area considered not to have a unique accent/dialect. I was secretly thinking, “what about California?” When I lived and waitressed in New Jersey they used to mock my accent, like theirs was so much better, lol. Funny how life will teach one how much they learned in school was pretty much garbage. Three hours away from me was the land of Pittsburghese. Yeah, right, I had no accent. I’m married to a native Californian now. He definitely doesn’t have an accent.
The Lake Michigan corridor is dominated by the very distinct Chicago accent (Where "z" sounds become "s" sounds at the end of nouns, and udder tings like dat, yuh know) once the flat Indiana twang has given way somewhere around Michigan City.
Further north and west around Huron/Superior (Wisconsin and Minnesota), the old Scandanavian inflections take hold as speakers develop a higher, more nasal register and a slight lilting cadence: "Whatever ya do, don' eat da lukefisk. It'll kill ya, quick, you betcha."
Californians speak with an accent, which is probably influenced by immigrants from the Midwest and South. Here is a list of words and how they are pronounced in California:
The only reason the Great Lakes are considered to have no accent is because that’s the accent radio and then TV decided to use, so it became the “generic American” accent, aka “no accent”. Everywhere has an accent, the only question is how much does it vary from “generic national”, which is still an accent even though we pretend it isn’t.