dialect tidbit

[Beverly Flanigan]

A student of mine from SW Virginia (Roanoke) gave me a phrase that first
sounds like a phatic greeting but really isn't:  "Good day!" or "Good day
in the morning time!" or "Great day (in the morning time)!"  It's really an
interjection, meaning "Wow! Gosh! Heck!" (her words).

Has anyone else heard of this expression?  The student's classmate from
northeastern Virginia was not familiar with it.  But the more I think of
it, the more it sounds vaguely like an Irish expression.  Ring a bell?