rest or rust

I heard a female news presenter (here in the sf bay area, knew 910) pronouncing 'rest' as 'rust'. This is due to Northern cities vowel shift. She could be from Upper midwest, who knows.

Here is more about NCVS.

http://en.wikipedia.org/wiki/Northern_cities_vowel_shift

Page 83 of

http://www-personal.umich.edu/~jlawler/210CourspackPart1.pdf