Who Speaks the Chicago Dialect?
Or rather, who doesn't? The answer, of course, is African Americans in the Chicago region, who have their own (and infinitely more interesting) dialect. Though this may be obvious.African Americans are the largest population group in Chicago, and it would be irresponsible to overlook the fact that the Chicago dialect is not used by the largest sector of the city's population.
Vowels
The most salient feature of the Chicago dialect is that it is undergoing the Northern Cities Vowel Shift. This is most noticeable in words with the /ae/ vowel, which gets "raised" so that it's close to /e/. Thus, 'bad' sounds a bit like 'bed,' or, 'beead.' Another notable aspect of this vowel shift is that /o/ is "fronted" so that it is closer to /ah/. So hot sounds a lttle like 'hat.' As an ongoing change, it is more prevalent and more pronounced among young people, middle-class people, and females, but it is quite widespread. nearly all white Chicagoans exhibit this vowel shift, at least to some extent. A more local vowel development is a monophthongization of /ow/ to /oh/, so that 'south' becomes 'soth' and 'down' becomes 'don.' This is more conservative and less widespread.
Also we can notice that when a vowel sound moves into another vowel’s territory, the result may be a merger —as when the sound of caught comes to be pronounced with the tongue in the same region of the mouth as for cot. In a different pattern, the movement of one vowel spurs a reactive movement in a neighboring vowel. As with strangers in an elevator, one vowel shifts to keep its distance when another enters the space.
These coordinated movements are heard in the Northern Cities