>> The southern accent seems to be merging with the midwestern accent in my area. <<
Sadly, the Southern Accent — or should one say, the Southern “Accents” in the plural — is/are dying. All across the Deep South, not to mention the Upper South, teenagers now ape the talk of Valley Girls and Britney Spears. In 75 years, the Southern accent will be heard only in old movies and recordings.
(This unfortunate development affects both the “drawl” variety and the “twang” variety of Southern speech, the latter being primarily from the Coastal Plain, lower Piedmont and “Delta” areas of the South, with the latter being primarily from the upper Piedmont and mountain areas.)
Back in the 80s I spent some time in Texas and noticed almost immediately that the local newsroom crew didn’t have the standard Texas accent that I heard in the stores and resturant.
On my way to Texas I stopped in Little Rock for the night and asked a gas station attendant if there were any decent cheap motels in the area. He said, “Taint none that’s fittin”. LOL
I think it is a natural consequence of technology. Accents and whole languages develop over time inside isolated populations. With the development of radio, TV, internet, air travel, and highways, there is no one in the US isolated enough to form or maintain an accent. About the only accents possible are now from bilingual speakers such as from Mexico or India.