Cool Dialect Map.

Patrick Madrid provides a cool dialect map so that we can see all the places where people talk funny.

For example, in many parts of the world, "dawn", "on", and "Don" do not rhyme, notwithstanding the fact that they do.  Apparently, San Francisco is one of those places.

The Central Valley has a purple line drawn around it, presumably because of the fact that in the Central Valley "possum" rhymes with "dinner."