In a segment discussing Josh McDaniels as a possibility for Green Bay, Carter on First Things First said the following about Harbaugh (forward to about 1:12 of the below video):

“Watch out for Jim Harbaugh. Because Jim Harbaugh potentially is trying to get his way out of Michigan. Alright, I’ve got good sources that are telling me not only Green Bay, but also watch out for the Cleveland Browns. He likes the quarterback situations there, and I believe that there is front office people in Green Bay who are enamored with Jim Harbaugh and potentially trying to get him to come to Green Bay.”

These guys get paid to mostly talk nonsense, but Jim Harbaugh back to the NFL seems pretty likely. 

His personality doesn’t work with college kids. 

Let’s see if CC’s sources pan out.